International Journal of Sport Nutrition and Exercise Metabolism, 2019, 29, 210-219
https://doi.org/10.1123/ijsnem.2018-0256© 2019 Human Kinetics, Inc.

SCHOLARLY REVIEWSpecial Environments: Altitude and Heat
Philo U. Saunders
Australian Institute of Sport and University of Canberra

Laura A. Garvican-Lewis
Australian Institute of Sport and Australian Catholic University

Robert F. Chapman
Indiana University

Julien D. Périard
University of Canberra
High-level athletes are always looking at ways to maximize training adaptations for competition performance, and using alteredenvironmental conditions to achieve this outcome has become increasingly popular by elite athletes. Furthermore, a series ofpotential nutrition and hydration interventions may also optimize the adaptation to altered environments. Altitude training was
ﬁrst used to prepare for competition at altitude, and it still is today; however, more often now, elite athletes embark on a series ofaltitude training camps to try to improve sea-level performance. Similarly, the use of heat acclimation/acclimatization to optimize
performance in hot/humid environmental conditions is a common practice by high-level athletes and is well supported in thescientiﬁc literature. More recently, the use of heat training to improve exercise capacity in temperate environments has been
investigated and appears to have positive outcomes. This consensus statement will detail the use of both heat and altitude training
interventions to optimize performance capacities in elite athletes in both normal environmental conditions and extreme
conditions (hot and/or high), with a focus on the importance of nutritional strategies required in these extreme environmental
conditions to maximize adaptations conducive to competitive performance enhancement.
Keywords: acclimatization, athletes, performance, training
Athletes in the sport of track and ﬁeld are often faced withtraining or competing in challenging environmental conditions.
The 2019 IAAF World Athletics Championships (Doha, Qatar) andthe 2020 Olympic Games (Tokyo, Japan) are anticipated to havethe highest heat index in the history of those respective events. The
IAAF World Cross Country Championships in 2015 (Guiyang,
China; elevation 1,275 m) and 2017 (Kampala, Uganda; elevation
1,210 m) were held at altitudes high enough to signiﬁcantly impair
aerobic performance. In the consensus statement, we will brieﬂy
discuss the physiological effects that the environments of heat/humidity and altitude have on track-and-ﬁeld performance and how
athletes and coaches can utilize altered environmental conditions toacclimatize and best prepare. With that background in hand, we
will share recommendations on speciﬁc nutritional interventions
that can be utilized to help optimize performance (both in training
Saunders and Garvican-Lewis are with Performance Services, Australian Institute ofSport, Canberra, Australian Capital Territory, Australia. Saunders and Périard arewith the University of Canberra Research Institute for Sport and Exercise(UCRISE), University of Canberra, Canberra, Australian Capital Territory,
Australia. Garvican-Lewis is also with the Mary MacKillop Institute for HealthResearch, Australian Catholic University, Melbourne, Victoria, Australia. Chapman
is with Human Performance Laboratory, Department of Kinesiology, Indiana
University, Bloomington, IN, USA. Saunders (philo.saunders@ausport.gov.au) is
the corresponding author.

210

and competition) in the adverse environmental conditions ofthermal load and altitude.

Heat Acclimation/Acclimatization forCompetition in the Heat
Acute exposure to hot and/or humid ambient conditions is wellknown to result in the development of thermal strain (i.e., elevatedskin, muscle, and core temperatures) during prolonged exercise and,
consequently, impair aerobic performance (Gonzalez-Alonso et al.,
1999; Périard & Racinais, 2016). This impairment is linked to athermoregulatory-mediated rise in circulatory and cardiovascularstrain that decreases maximal aerobic capacity (VO2max; Ely et al.,2010; Périard & Racinais, 2015; Périard et al., 2011) and a potential
hyperthermia-induced reduction in voluntary drive (i.e., motivation;
Febbraio et al., 1994, 1996). Heat stress exercise also leads to agreater reliance on muscle glycogen and anaerobic metabolism(Febbraio et al., 1994, 1996), which may deplete endogenous storesof glycogen. Along with inﬂuencing performance, the developmentof hyperthermia increases the risk of experiencing exertional heat
illness, which is a serious health hazard leading to more deaths than
all other natural disasters combined (Leon & Bouchama, 2015).
Notwithstanding, when repeatedly exposed to conditions that elicit
profuse sweating and elevate whole-body temperature, adaptations

Downloaded by on 04/17/19

Heat and Altitude Training

develop that reduce the deleterious effects of heat stress. Heatacclimation and acclimatization, which refer to periods of heat
exposure undertaken in artiﬁcial (laboratory) or natural (outdoor)
settings, respectively, lead to improved submaximal exercise performance, increased VO2max, and improved thermal comfort in theheat (Periard et al., 2015; Sawka et al., 2011). These beneﬁts areachieved through enhanced sweating and skin blood ﬂow responses, plasma volume expansion, better ﬂuid balance (hydration),and cardiovascular stability, as well as acquired thermal tolerance(Periard et al., 2016; Tyler et al., 2016).
Adaptations to the heat are generally achieved through four
broad induction pathways: (a) constant work rate exercise, (b) selfpaced exercise, (c) controlled hyperthermia or isothermic heatacclimation, and (d) controlled heart rate (relative intensity) heatacclimation (Daanen et al., 2018). While these approaches all havemerit and induce heat adaptations, exercise–heat acclimatization
has been purported to provide more speciﬁc responses due toexposure to the exact conditions that will be encountered during
training or competition (i.e., exercise task, solar radiation, windspeed, and terrain/geography; Periard et al., 2015). The time courseof heat acclimation/acclimatization has been demonstrated to berelatively rapid, with a signiﬁcant fraction of the adaptations
developing during the ﬁrst week of heat exposure, and 10–14
days being optimal for complete or near-complete acclimation/acclimatization (Periard et al., 2015, 2016; Tyler et al., 2016).
Interestingly, the rate of decay for the main adaptive beneﬁts(i.e., lowered heart rate and core temperature during exercise) is
2.5% per day without heat exposure (Daanen et al., 2018). As such,athletes tapering for a major race after a heat acclimation/acclimatization regimen may lose 35% of their adaptations after 2 weeks
without heat exposure. Training regularly has been suggested to aid
in maintaining adaptation, however, as athletes can achieve highcore temperatures and sweat rates when training vigorously, evenin cooler climates. Therefore, it is recommended to complete an
acclimatization regimen as close as possible to the competition
being held in the heat.

Heat Training for Improved Performance inTemperate Conditions
In recent years, there has been a noticeable shift in trying to use heatacclimation to provide an added beneﬁt to performance in cool
conditions. There have been reported improvements in VO2max inuntrained (13%) and unﬁt (23%) individuals in cool conditions
after 8 days of working in the heat (Shvartz et al., 1977) and anincrease (32%) in running time to exhaustion following postexercise sauna bathing (Scoon et al., 2007); although others havereported no improvements (Keiser et al., 2015) or inconclusiveﬁndings (Neal et al., 2016a).
The mechanisms modulating the potential transfer of adaptations and performance improvements between hot and cool conditions remain unresolved, but could be linked to a variety ofergogenic responses, such as cardiovascular, thermoregulatory,
and cellular adaptations. For example, an increase in plasma
volume resulting from chronic bouts of exercise in the heat may
decrease whole blood viscosity, which has been shown to havepositive effects on endurance performance (Telford et al., 1994).
Adaptations from training in hot conditions may also allow athletes
to train at any given speed with a lower heart rate and core bodytemperature, both factors being associated with improved exercise
economy (Thomas et al., 1995). This is supported by ﬁndings from

211

Lorenzo et al. (2010) of increased performance in a cool environment following heat acclimation being associated with improved
economy, lactate threshold, and cardiac performance. Accordingly,
heat acclimation may provide a stimulus for enhancing performance in nonthermally challenging environments by improving
VO2max, lactate threshold, and exercise economy (Corbett et al.,2014). It has also been suggested that heat acclimation may
preserve or enhance performance at altitude (White et al., 2014).
The purported pathways for such a response include plasma
volume expansion and improved cardiac efﬁciency, and involvethe upregulation of hypoxia-inducible factor-1 in boosting oxygen
delivery. Additional research is required, however, to thoroughly
elucidate the mechanisms associated with improvements in performance in cool conditions and at altitude, as well as to fully
substantiate the ergogenic cross-beneﬁts of heat training on performance in these environments (Lee et al., 2016; McCleave et al.,2017; White et al., 2016).

Periodization of Heat Training Within a
SeasonA key question for elite athletes regarding the implementation ofheat training is when to schedule it in the overall training program
and, in particular, ahead of competing in the heat. Prior to a major
competition, most athletes will undertake a block of training inwhich the volume and/or intensity are increased, followed by aperiod of taper. It has been suggested that a 1- to 2-week heatacclimation regimen with the controlled heart rate approach(Periard et al., 2015) can be used as part of the training program
4–6 weeks prior to competition, providing a constant stimulus foradaptation and minimally affecting regular training. This could
then be supplemented with regular passive heat exposure during the
weeks prior to competition, or a short (2–4 days) reacclimation
period the week before competition (Figure 1). This is suggested
because a reacclimation regimen, when undertaken within a monthof the original acclimation protocol, leads to a faster (re)inductionof adaptations (Daanen et al., 2018).
While exercise–heat exposure during the taper may help
maintain the beneﬁts of heat acclimation, it may also interferewith the goal to reduce the overall training load. Passive heat
exposure (e.g., sauna or hot bath) following a training session in acool climate (Stanley et al., 2015; Zurawlew et al., 2016) may thus
be preferred during the taper. Given the risk of losing some of theexercise adaptations, maintaining some “easy” exercise sessions in
the heat during the taper period may help to better maintain
adaptations prior to competing in the heat. Figure 1 summarizes
some of the different approaches that can be adopted in preparing
for competition in the heat based on available time, resources, andarrival at the competition venue.

Nutrition for Training in the Heat
Carbohydrate requirements for exercise are increased in the heat
due to a shift in substrate utilization toward carbohydrate oxidation(Febbraio, 2001). Daily food patterns should focus on replacing
glycogen stores after exercise. Competition strategies should
include activities to enhance carbohydrate availability, such asbuilding up glycogen stores in preparation for endurance events,
pre-event carbohydrate intake, and intake of glucose/electrolytes in
events lasting longer than 60 min. This can be done using water andthe carbohydrate gel preparations or using sports drinks. It has been

IJSNEM Vol. 29, No. 2, 2019

212

IJSNEM Vol. 29, No. 2, 2019

Figure 1 — Strategies for inducing heat adaptations ahead of major competitions based on arriving at the event location early (1–2 weeks) or late (1–3 days) in relation to competition day.
Athletes arriving early can (A) initiate the adaptation process by conducting one to two heat exposure sessions per week for 4–8 weeks prior to traveling and then training outdoors in the heat once
on site or (B) undertake 7–14 days of heat acclimation 4–6 weeks before departure followed by a heat exposure maintenance session(s) per week prior to traveling and then training outdoors in theheat once on site. Athletes arriving late can (C) heat acclimate for 7–14 days 2–3 weeks before traveling and conduct a heat exposure maintenance session(s) in the taper week prior to traveling or(D) extend this approach by heat acclimating 4–6 weeks before departure and performing a short (3–4 days) reacclimation protocol the week prior to traveling. The heat acclimation maintenancesessions in Strategy B (Weeks 3, 2, and 1), C (taper week), and D (Weeks 3, 2, and 1) are not required, but will help maintain adaptations. Based on individual circumstances (e.g., training phase,workout, facilities, logistical support), a particular approach or combination of heat acclimation regimens and individual heat training sessions can be used to induce adaptations.

Downloaded by on 04/17/19

Downloaded by on 04/17/19

Heat and Altitude Training

reported that an intake of carbohydrates prior to and during
prolonged exercise in the heat provides beneﬁts to exercise performance (Burke et al., 2005).
Hydration in hot/humid conditions is critical to maximize
performance during training and competition. Athletes should,
therefore, undertake endurance events in a rested, well-fed, andwell-hydrated state (Racinais et al., 2015). They may, thus, consume 5–6 ml of water per kilogram of body mass every 2–3 hr prior
to training or competing in the heat, having tested this strategy
prior to racing in a major competition to establish volume needs.
During exercise, it is advisable to minimize body mass losses
induced via sweating, while using caution to avoid overdrinking.
Those who sweat profusely may require supplementing their ﬂuids
with additional sodium (e.g., 3.0 g of salt added to 0.5 L of acarbohydrate-electrolyte solution). From a practical perspective, it
was recently highlighted that high-intensity exercise in whichsweat rate is elevated, along with activities lasting >90 min in
the heat, should be accompanied with a planned hydration strategy(Keneﬁck, 2018). In contrast, drinking to thirst may be sufﬁcient tooffset ﬂuid losses during low-intensity exercise of shorter duration(<90 min) in cool climates. Recovery of signiﬁcant ﬂuid loss after
exercise is assisted by the simultaneous replacement of electrolyte
loss. Sports drinks (e.g., ﬂavored drinks consisting of water, somesalt, and sugar) allow more complete hydration than drinking plain
water or soft drinks because they have optimal sugar concentrations
to maximize the uptake of water by the body. Consuming a
combination of ﬂuids and solid foods is also advisable for rehydration and electrolyte replacement.
The notion that permissive dehydration or restricted ﬂuid
consumption may enhance the adaptive response (e.g., plasma
volume expansion) during chronic heat exposure has recently been
explored. Although pathway(s) via which this might be achieved
have been proposed (i.e., increased ﬂuid regulatory, thermal, andcardiovascular strain), contention currently exists regarding the
efﬁcacy of this approach (Garrett et al., 2014; Neal et al., 2016b;
Pethick et al., 2019). Additional studies are, therefore, warranted to
fully elicit whether this practice is efﬁcacious at enhancing adaptation or potentially deleterious in optimizing performance gains
through compromised heat training sessions (i.e., lower workloads). Further examination is also required as to whether protein
and carbohydrate supplementation during heat acclimation enhances plasma volume expansion by increasing plasma albumin
content, leading to enhanced thermoregulatory responses andattenuated cardiovascular strain (Goto et al., 2010).

Altitude Training for Improved Training andCompetition in Normoxia
Adaptation to Altitude
Physiologically, endurance exercise performance at altitude is primarily affected by a reduction in oxygen delivery to the musculature(Chapman, 2013). Within minutes of exposure to altitude, theelegant design of the human body induces acclimatization responses
that are largely dependent on the severity and duration of the altitude
exposure (Fulco et al., 1998), as well as individual response
characteristics (Chapman et al., 1998). Adaptation to a hypoxic
environment results in a variety of physiological responses thathave the potential to increase endurance performance at sea level(Saunders et al., 2009a). While an altitude-induced acceleration of
red blood cell production resulting in an increase in total hemoglobin
mass (Hbmass) is often considered the primary mechanism by which213

altitude training improves endurance performance (Levine & StrayGundersen, 2005), a number of nonhematological adaptations may
be equally as important (Gore et al., 2007), including improved
running economy (Saunders et al., 2004, 2009c) and buffering
capacity (Gore et al., 2001). Thus, understanding the timing ofpeak performance following altitude training is increasingly difﬁcult,given the expected differences in the time course of decay for each
adaptation.

Altitude Training Modalities
Altitude training, in various forms, has grown in popularity sincethe 1968 Olympic Games were held in Mexico City at >2,000 m, somuch so that elite endurance athletes who choose not to use someform of altitude training within their preparation are often in theminority among the athletic community. With growing advances intechnology, so too are the options for incorporating various modalities of altitude training into the training plan, even for sea-level
dwellers including altitude chambers and altitude tents for passive
and active exposure to altitude. While the efﬁcacy of altitude training
for improved performance at sea level is still debated among thescientiﬁc community (Lundby & Robach, 2016; Millet et al., 2017),
much of the attention now has turned to the optimization of eachmethod.
Traditional altitude training methods (classical/traditional/live
high:train high [LHTH]), born out of the routine practice of altitude
natives, involve living and training continuously at natural altitudes
usually between 1,500 and 3,000 m (Friedmann-Bette, 2008;
Saunders et al., 2009a). Often termed LHTH, natural altitude training
camps can range from 2 to 6 weeks and are often repeated multiple
times throughout a year. The ideal elevation depends greatly upon
the logistics and facilities associated with each location, but recent
research suggests that 2,000–2,200 m provides an optimal balance
between the hypoxic dose (Garvican-Lewis et al., 2016b) andtraining quality (Sharma et al., 2017). Traditional altitude training
remains a staple in the endurance athlete’s training preparation, andthe current scientiﬁc literature supports anecdotal claims ofimproved sea-level performance (Bonetti & Hopkins, 2009).
Live high:train low was popularized in the 1990s, and it
combines sleeping at altitude with training conducted either at sea
level or substantially lower altitudes (Levine & Stray-Gundersen,1997). The purported beneﬁts of LHTL are that the hypoxic dose(and thus associated adaptations) can be maximized withoutcompromising training quality (Levine & Stray-Gundersen, 1997).
LHTL can be achieved either using suitable natural altitude training
locations that allow relatively easy access to lower level training
locations or, more commonly, using simulated altitude chambers or
tents. Simulated altitude can be achieved via nitrogen dilution or
oxygen ﬁltration and presents a viable option for athletes fromcountries lacking suitable terrestrial training locations. The total
hypoxic dose is an important consideration for those engaging in
LHTL, since daily exposure is less than for those engaging in LHTH.
Typically, 3–4 weeks at a simulated altitude of 3,000 m, averaging 14
hr of exposure per day, is recommended (Clark et al., 2009), equating
to a total hypoxic dose of 882–1,176 km·hr (Garvican-Lewis
et al., 2016b).

Altitude Training for Competition at Altitude
In track-and-ﬁeld endurance events (e.g., marathon and race walking), it is well established that performance at altitude is impaired.
For the athlete, coach, or clinician, there are established and

IJSNEM Vol. 29, No. 2, 2019

214

Saunders et al.

emerging evidence-based outcomes regarding practical implementation procedures that can help mitigate (but not wholly eliminate)
the decline in performance when competing at altitude. First, ageneral understanding of the speciﬁc acclimatization effects that
occur with altitude exposure, as well as the timing of thoseadaptations, allows for proper interventions to maximize positive
adaptations and avoid negative ones. Second, there are a number oflogistical planning choices under the control of the athlete/coach/clinician, each of which can strongly affect performance at altitudewith both acute and chronic exposure.

Acclimatization Responses With Altitude Exposure

Downloaded by on 04/17/19

Interestingly, for performance at altitude following relatively shortdurations (<72 hr) of exposure to altitude, the well-known acclimatization response of an acute increase in erythropoietin has little
inﬂuence (Lundby & Damsgaard, 2006); however, longer term
effects of an increase in total Hbmass appear to mitigate the VO2max
decrement with acute exposure to low and moderate altitudes(Robach et al., 2008). Generally, the higher an athlete resides,
the greater the magnitude of the physiological altitude acclimatization response (Fulco et al., 1998); however, simply living at ahigher altitude does not appear to acutely accelerate the process ofaltitude acclimatization and actually causes greater performance
impairment in the ﬁrst few days at altitude (Chapman et al., 2016).

Periodization of Altitude Training
Within a Season
When determining when to use altitude training in a yearly plan,
there are a number of factors to consider. The severity of altitude,
time spent training at altitude, history of altitude training, timing oftraining leading into competition, whether there is a lower altitude
training option, and the type of altitude used are all importantfactors to consider to maximize the beneﬁts of altitude training.
For elite endurance athletes, altitudes of 1,800–2,500 m areconsidered optimal for classical altitude training (Saunders et al.,2009a). Altitudes much lower than this do not appear to provide
sufﬁcient hypoxic stimulus for key physiological adaptation,although increases in Hbmass have been reported from training
as low as 1,600 m (Sharma et al., 2019) and 1,800 m (GarvicanLewis et al., 2015). Altitudes much higher than 2,500 m havegreater potential to cause overtraining and compromise the abilityof an athlete to absorb and respond to the hypoxic and training
stimuli (Saunders et al., 2009a).
The time spent at altitude is an important factor, as there is no
point making the effort to travel and train at altitude if the length of
exposure is insufﬁcient to stimulate worthwhile adaptations. It has
been recommended to go for 3–4 weeks when using altitude
training to improve sea-level performance (Rusko et al., 2004).
Recently, a new metric for the hypoxic dose was proposed whereby
the total hypoxic dose (in km·hr) is calculated as the elevation (m)/hours of exposure × 1,000 (Garvican-Lewis et al., 2016b), with theminimum threshold for Hbmass adaptation appearing to be∼500 km·hr. However, the optimal dose for nonhematologicalbeneﬁts associated with altitude, as well as any potential additiveeffects of several hypoxic exposures within a season, requires
further investigation. It is recommended that athletes based at sea
level spend no more than 2 months at altitude at any one time
and that it is more beneﬁcial for athletes to undertake short blocks(2–6 weeks) more frequently throughout the year, with two to three
stints being optimal.

It has been suggested that longer than 8 weeks is required
between altitude training stints to maximize the training afterward(Robertson et al., 2010). A longer time between altitude exposures
also ensures that athletes are not excessively fatigued going into a
subsequent altitude training camp, training phase, or competition.
There is also a belief that every subsequent camp at altitude has someform of memory, with training seemingly easier each time an athlete
undertakes a training camp at altitude, and potentially, adaptations
are better when using altitude repeatedly. As an example, Hbmass wasmeasured in elite swimmers over a 4-year period with multiple
altitude camps during this period; all swimmers had a linear increasein Hbmass, with the resultant increase from the end to the start ∼10%
(Figure 2). Further work in this area is required to gain somegrounded evidence in the area of multiple altitude exposures.
The periodization of the training year and the training phaseprior to an altitude camp are other factors that should be considered.
The emphasis of training can be tailored to meet the demands of the
training phase of the athletes. For example, in the early build-up
period, where athletes are trying to increase the volume of training
and high-quality training is not as critical, a longer period of altitude
training can be undertaken where the focus is on accumulating ahigh volume of training utilizing the hypoxic stimulus, rather thanperforming high-intensity training. Low- to moderate-altitude training during a competitive season has been used in elite middledistance runners (Saunders et al., 2009b). In this particular study,
seven runners lived at ∼1,800 m and did all their low- to moderateintensity running at 1,700–2,200 m. However, because the athletes
were in their competitive season, they completed all high-quality
sessions at 900-m altitude to maintain the 800/1,500-m race-paceinterval training required to stay race ﬁt. This protocol resulted
in an improved competitive performance by ∼2% (Saunders et al.,2009b).
The additional “load” imposed by training at altitude (LHTH)
should not be forgotten when designing an altitude training program. While elite athletes with prior altitude experience are likely
to handle a normal volume and intensity of training, dramaticincreases in overall load are not recommended (Saunders et al.,2009a). To avoid a reduction in race-speciﬁc ﬁtness, athletesshould undertake a series of shorter race-pace efforts where
velocity is not compromised or possibly enhanced due to the
reduced air density (Peronnet et al., 1991) and have longer
recoveries than at sea level to maintain speed during the entire
training session. From experience, at an altitude of ∼2,000 m, themaximal interval distance that can be performed at middle distance(800–1,500 m) race pace is ∼600 m, and recovery times probably
need to be multiplied by 1.5–2.0 when compared with the sameinterval sessions performed at sea level. With acclimatizationand partial restoration of VO2max at altitude, the duration of theinterval efforts can be increased and/or the recovery times
decreased. Recent work has demonstrated that running speed
during threshold and VO2max intensity training sessions areadversely affected at 2,100-m altitude by 6% and 4%, respectively,
equating to 13 and 6 s/km at the speeds at which elite middledistance runners train (Sharma et al., 2017). These ﬁndings indicatethat descending to a lower altitude (if possible) is beneﬁcial for
threshold and VO2max sessions in order to maximize the O2 ﬂux.
With regard to LHTL altitude exposure, even though theability to train at or near sea level allows athletes to maintain ahigher level of training, the extra stress of living at moderate
altitude for most of the day makes training harder and the athletes
generally more tired during the LHTL stint. For athletes spending
3 weeks of 14 hr/day at 3,000 m, training is generally harder, andIJSNEM Vol. 29, No. 2, 2019

Downloaded by on 04/17/19

Heat and Altitude Training

215

Figure 2 — Progression of Hbmass in four elite Australian swimmers over a 4-year period. All data are absolute Hbmass in grams over eight altitude
camps, including both LHTL in Canberra (3,000/600 m) and LHTH in Sierra Nevada, Spain (2,300 m). LHTH = live high:train high (natural);
LHTL = live high:train low (natural or simulated); Hbmass = hemoglobin mass.

modiﬁcations are often required to ensure athletes do not overreach
during this period. Optimizing recovery and making some modiﬁcations to training intensity during the ﬁrst half of an LHTL camp
are both ways to maximize training quality and minimize fatigue
levels during such a camp.
The optimal timing of competition after altitude training has
not been fully elucidated. Traditional research has focused on
performance immediately following exposure (1–2 days post).
Interestingly, despite Hbmass returning to baseline levels after
4 weeks at sea level (Prommer et al., 2010), performance improvements following a properly executed altitude training camp havebeen shown to be preserved (McLean et al., 2013b). These outcomes suggest that, in order to achieve peak performance following
an altitude camp, it is important to appropriately modify training ina similar manner to a typical taper. If an athlete is competing in thedays immediately following the descent, then the last few days to a
week at altitude will need to be lighter in order to allow the athlete
to freshen up before the descent. If the competition is delayed, thenan appropriate recovery block at sea level is necessary to absorb thetraining and adaptations induced at altitude. Usually, this is just a
few days to get over travel fatigue and the general fatigue fromtraining at altitude. This period after altitude is the best time to gethigh-quality training (particularly higher intensity training rather
than increased volume) done, as athletes can train at a higher level
than before because of the increased physiological capacities

obtained from altitude training. Many athletes ﬁnd that, during
training in the 4–6 weeks postaltitude, they are able to train at ahigher level, leading to improved race performance following thisblock of training (Chapman et al., 2014). This concept is far fromnew, as in some of the original works from the 1980s examining theeffect of blood doping on endurance exercise performance, maximal oxygen uptake in a group of highly trained distance runners
remained signiﬁcantly improved 16 weeks after an infusion of
two units of whole blood (Buick et al., 1980). It is generally
understood that the increased over time while in the blood-doped
condition may have allowed for other physiological adaptations
which maintained performance, despite the normalization of red
blood cell mass in a fraction of the 16-week time period (Chapman
et al., 2014). This concept is also related to a key premise behindthe low-altitude training portion of the LHTL altitude training
paradigm. By training at low altitude, the athlete is able to train at
faster speeds and achieve a higher O2 ﬂux between the muscle
capillary and mitochondria compared with training at higher
altitudes (Levine & Stray-Gundersen, 1997). This higher oxygen
ﬂux with low-altitude training is believed to be a primary stimulus
behind the improved mean steady-state workload improvement inathletes who live high and train low (Levine & Stray-Gundersen,1997). Figure 3 presents how altitude can be structured into acompetition year based on the outcome of the camp or multiple camps.

IJSNEM Vol. 29, No. 2, 2019

Downloaded by on 04/17/19

216

Saunders et al.

Figure 3 — Sample periodization of altitude training within a season. LHTH = live high:train high (natural); LHTL = live high:train low (natural or
simulated). Gray boxes indicate potential outcomes of proposed altitude block, relative to the time in the season. *Recommendation for competition
conducted at altitude.

Optimizing Adaption to Altitude
Athletes can increase the chances of optimal adaptation to altitude
by ensuring that a number of appropriate steps (several nutrition
based) are taken in the design and implementation of each altitude
training camp.
a. Iron: Iron is an essential component of red blood cells
and hence iron requirements are increased at altitude. Iron
supplementation appears necessary for optimal adaptation(Garvican-Lewis et al., 2016a, 2018), with greater gains in
Hbmass observed in athletes who were supplemented duringexposure compared with those who were not (Govus et al.,2015). Furthermore, a blunted Hbmass response was observedin nonsupplemented athletes despite their being iron replete(Garvican-Lewis et al., 2018), providing further support for
the notion that iron supplementation during exposure is more
important than prealtitude ferritin stores (Garvican-Lewis
et al., 2016a). Consequently, following a pre-altitude blood
test 1–2 weeks before altitude and medical review, daily
oral iron supplementation (50–100 mg of elemental iron)for the majority of athletes is recommended throughout
altitude exposure to support erythropoiesis. Optimizationof the dosing strategy employed (e.g., split vs. single doses,
or alternate day vs. every day) warrants further investigation
in athletic cohorts.
b. Energy intake: A restricted energy intake combined with hightraining load at altitude (Woods et al., 2017a) has thepotential to compromise energy availability, which in turn
may inhibit erythropoietic adaptation to altitude, as well as
overall health and well-being (Heikura et al., 2018; McLean
et al., 2013a). Athletes are advised to maintain a balanced dietand support training with appropriate fuel and ﬂuid intake.
Hydration practices should counterbalance the increased
ﬂuid loss via ventilation and diuresis, although consumptionof large volumes in the evening should be avoided to reducenight waking to pass urine. Macronutrient requirements andoverall caloric intake need to be increased at altitude due toa likely increased resting metabolic rate, although it must be
noted that further validation is required, since, to date, anincreased resting metabolic rate has only been observed ina very small cohort of runners at 2,000 m (Woods et al.,2017b). Furthermore, using altitude as a means to actively
decrease body mass in a competition phase is not recommended, since Hbmass responses may be compromised(McLean et al., 2013a).
c. Training load/periodization: Particular attention to thetraining load directly prior to the altitude training block(the “lead-in phase”), training appropriately while at altitude(as detailed in the periodization section above), and commencing an appropriate taper during the ﬁnal stages of thecamp are crucial to successful performance immediately
following altitude.
d. Illness/inﬂammation: Athletes with signiﬁcant illness or
injury appear compromised in their adaptation to altitude

IJSNEM Vol. 29, No. 2, 2019

Heat and Altitude Training(Gore et al., 1998; Heikura et al., 2018; Wachsmuth et al.,2013), and therefore, altitude training may need to be delayedor modiﬁed if illness and injury is present. Appropriate
hygiene practices are strongly recommended during an altitude camp.

Downloaded by on 04/17/19

Conclusion
The use of altitude and heat as interventions to prepare forcompetitions in these conditions is essential and supported by alarge body of evidence. Altitude training in particular further
provides performance beneﬁts for competition in normal environmental conditions (i.e., sea level), with heat training possibly aiding
performance in the cool environment. It seems sensible for coaches
and elite athletes, especially on the endurance side of athletics, toinvestigate the use of altitude and heat training. In recent times, it
has been widely discussed whether the concurrent use of heat andaltitude enhances the potential adaptations from both training
methods and results in even greater performance outcomes thantheir independent use. Altitude training can provide an increased
oxygen-carrying capacity, a more efﬁcient use of oxygen, and abetter ability to tolerate anaerobic metabolism; heat training has theability to increase plasma volume and reduce cardiovascular andthermoregulatory strain. It is recommended to focus on the intervention most relevant to competition and ensure that training,
nutrition, and recovery are optimized to allow positive training
adaptations and, ultimately, performance enhancement.

References
Bonetti, D.L., & Hopkins, W.G. (2009). Sea-level exercise performance
following adaptation to hypoxia: A meta-analysis. Sports Medicine,39(2), 107–127. PubMed ID: 19203133 doi:10.2165/00007256200939020-00002
Buick, F.J., Gledhill, N., Froese, A.B., Spriet, L., & Meyers, E.C. (1980).
Effect of induced erythrocythemia on aerobic work capacity. Journalof Applied Physiology: Respiratory, Environmental and Exercise
Physiology, 48(4), 636–642. doi:10.1152/jappl.1980.48.4.636
Burke, L.M., Wood, C., Pyne, D.B., Telford, D.R., & Saunders, P.U.
(2005). Effect of carbohydrate intake on half-marathon performanceof well-trained runners. International Journal of Sport Nutrition andExercise Metabolism, 15(6), 573–589. PubMed ID: 16521844 doi:10.
1123/ijsnem.15.6.573
Chapman, R.F. (2013). The individual response to training and competition at altitude. British Journal of Sports Medicine, 47(Suppl 1),i40–i44. doi:10.1136/bjsports-2013-092837
Chapman, R.F., Karlsen, T., Ge, R.L., Stray-Gundersen, J., & Levine, B.D.
(2016). Living altitude inﬂuences endurance exercise performancechange over time at altitude. Journal of Applied Physiology, 120(10),1151–1158. doi:10.1152/japplphysiol.00909.2015
Chapman, R.F., Laymon Stickford, A.S., Lundby, C., & Levine, B.D.
(2014). Timing of return from altitude training for optimal sea level
performance. Journal of Applied Physiology, 116(7), 837–843.
doi:10.1152/japplphysiol.00663.2013
Chapman, R.F., Stray-Gundersen, J., & Levine, B.D. (1998). Individual
variation in response to altitude training. Journal of Applied Physiology, 85(4), 1448–1456. PubMed ID: 9760340 doi:10.1152/jappl.
1998.85.4.1448
Clark, S.A., Quod, M.J., Clark, M.A., Martin, D.T., Saunders, P.U., &Gore, C.J. (2009). Time course of haemoglobin mass during 21 days
live high:train low simulated altitude. European Journal of Applied

217

Physiology, 106(3), 399–406. PubMed ID: 19294411 doi:10.1007/
s00421-009-1027-4
Corbett, J., Neal, R.A., Lunt, H.C., & Tipton, M.J. (2014). Adaptation toheat and exercise performance under cooler conditions: A new hot
topic. Sports Medicine, 44(10), 1323–1331. PubMed ID: 24943043
doi:10.1007/s40279-014-0212-8
Daanen, H.A.M., Racinais, S., & Periard, J.D. (2018). Heat acclimation
decay and re-induction: A systematic review and meta-analysis.
Sports Medicine, 48(2), 409–430. doi:10.1007/s40279-017-0808-x
Ely, B.R., Cheuvront, S.N., Keneﬁck, R.W., & Sawka, M.N. (2010). Aerobic
performance is degraded, despite modest hyperthermia, in hot environments. Medicine & Science in Sports & Exercise, 42(1), 135–141.
PubMed ID: 20010120 doi:10.1249/MSS.0b013e3181adb9fb
Febbraio, M.A. (2001). Alterations in energy metabolism during exercise
and heat stress. Sports Medicine, 31(1), 47–59. PubMed ID:
11219501 doi:10.2165/00007256-200131010-00004
Febbraio, M.A., Carey, M.F., Snow, R.J., Stathis, C.G., & Hargreaves, M.
(1996). Inﬂuence of elevated muscle temperature on metabolism
during intense, dynamic exercise. American Journal of Physiology,271(5 Pt 2), R1251–R1255. PubMed ID: 8945960
Febbraio, M.A., Snow, R.J., Hargreaves, M., Stathis, C.G., Martin, I.K., &Carey, M.F. (1994). Muscle metabolism during exercise and heatstress in trained men: Effect of acclimation. Journal of Applied
Physiology, 76(2), 589–597. doi:10.1152/jappl.1994.76.2.589
Friedmann-Bette, B. (2008). Classical altitude training. Scandinavian
Journal of Medicine & Science in Sports, 18(Suppl. 1), 11–20.
doi:10.1111/j.1600-0838.2008.00828.x
Fulco, C.S., Rock, P.B., & Cymerman, A. (1998). Maximal and submaximal exercise performance at altitude. Aviation, Space, and Environmental Medicine, 69(8), 793–801. PubMed ID: 9715971
Garrett, A.T., Goosens, N.G., Rehrer, N.J., Patterson, M.J., Harrison, J.,
Sammut, I., & Cotter, J.D. (2014). Short-term heat acclimation iseffective and may be enhanced rather than impaired by dehydration.
American Journal of Human Biology, 26(3), 311–320. PubMed ID:
24469986 doi:10.1002/ajhb.22509
Garvican-Lewis, L.A., Govus, A.D., Peeling, P., Abbiss, C.R., & Gore,
C.J. (2016a). Iron supplementation and altitude: Decision making
using a regression tree. Journal of Sports Science and Medicine,
15(1), 204–205.
Garvican-Lewis, L.A., Halliday, I., Abbiss, C.R., Saunders, P.U., & Gore,
C.J. (2015). Altitude exposure at 1800 m increases haemoglobin massin distance runners. Journal of Sports Science and Medicine, 14(2),413–417. PubMed ID: 25983592
Garvican-Lewis, L.A., Sharpe, K., & Gore, C.J. (2016b). Time for a
new metric for hypoxic dose? Journal of Applied Physiology, 121(1),352–355. doi:10.1152/japplphysiol.00579.2015
Garvican-Lewis, L.A., Vuong, V.L., Govus, A.D., Peeling, P., Jung, G.,
Nemeth, E., . . . Gore, C.J. (2018). Intravenous iron does not augment
the hemoglobin mass response to simulated hypoxia. Medicine &Science in Sports & Exercise, 50(8), 1669–1678. PubMed ID:
29538179 doi:10.1249/MSS.0000000000001608
Gonzalez-Alonso, J., Teller, C., Andersen, S.L., Jensen, F.B., Hyldig, T.,& Nielsen, B. (1999). Inﬂuence of body temperature on the development of fatigue during prolonged exercise in the heat. Journal ofApplied Physiology, 86(3), 1032–1039. PubMed ID: 10066720
doi:10.1152/jappl.1999.86.3.1032
Gore, C.J., Clark, S.A., & Saunders, P.U. (2007). Nonhematologicalmechanisms of improved sea-level performance after hypoxic exposure. Medicine & Science in Sports & Exercise, 39(9), 1600–1609.
PubMed ID: 17805094 doi:10.1249/mss.0b013e3180de49d3
Gore, C.J., Hahn, A., Rice, A., Bourdon, P., Lawrence, S., Walsh, C., . . .
Gore, C. (1998). Altitude training at 2690m does not increase total

IJSNEM Vol. 29, No. 2, 2019

Downloaded by on 04/17/19

218

Saunders et al.

haemoglobin mass or sea level VO2max in world champion trackcyclists. Journal of Science and Medicine in Sport, 1(3), 156–170.
PubMed ID: 9783517 doi:10.1016/S1440-2440(98)80011-X
Gore, C.J., Hahn, A.G., Aughey, R.J., Martin, D.T., Ashenden, M.J.,
Clark, S.A., . . . McKenna, M.J. (2001). Live high:train low increases
muscle buffer capacity and submaximal cycling efﬁciency. Acta
Physiologica Scandinavica, 173(3), 275–286. PubMed ID: 11736690
doi:10.1046/j.1365-201X.2001.00906.x
Goto, M., Okazaki, K., Kamijo, Y., Ikegawa, S., Masuki, S., Miyagawa,K., & Nose, H. (2010). Protein and carbohydrate supplementation
during 5-day aerobic training enhanced plasma volume expansion
and thermoregulatory adaptation in young men. Journal of Applied
Physiology, 109(4), 1247–1255. doi:10.1152/japplphysiol.00577.
2010
Govus, A.D., Garvican-Lewis, L.A., Abbiss, C.R., Peeling, P., & Gore,
C.J. (2015). Pre-altitude serum ferritin levels and daily oral ironsupplement dose mediate iron parameter and hemoglobin mass
responses to altitude exposure. PLoS ONE, 10(8), e0135120. PubMed
ID: 26263553 doi:10.1371/journal.pone.0135120
Heikura, I.A., Burke, L.M., Bergland, D., Uusitalo, A.L.T., Mero, A.A., &Stellingwerff, T. (2018). Impact of energy availability, health, and sex
on hemoglobin-mass responses following live-high-train-high altitude training in elite female and male distance athletes. International
Journal of Sports Physiology and Performance, 13(8), 1090–1096.
PubMed ID: 29431548 doi:10.1123/ijspp.2017-0547
Keiser, S., Fluck, D., Huppin, F., Stravs, A., Hilty, M.P., & Lundby, C.
(2015). Heat training increases exercise capacity in hot but not in
temperate conditions: A mechanistic counter-balanced cross-overstudy. American Journal of Physiology. Heart and Circulatory
Physiology, 309(5), H750–H761. PubMed ID: 26150574
Keneﬁck, R.W. (2018). Drinking strategies: Planned drinking versus
drinking to thirst. Sports Medicine, 48(Suppl. 1), 31–37. PubMed
ID: 29368181 doi:10.1007/s40279-017-0844-6
Lee, B.J., Miller, A., James, R.S., & Thake, C.D. (2016). Cross acclimation
between heat and hypoxia: Heat acclimation improves cellular
tolerance and exercise performance in acute normobaric hypoxia.
Frontiers in Physiology, 7, 78. PubMed ID: 27014080
Leon, L.R., & Bouchama, A. (2015). Heat stroke. Comprehensive Physiology, 5(2), 611–647. PubMed ID: 25880507 doi:10.1002/cphy.
c140017
Levine, B.D., & Stray-Gundersen, J. (1997). “Living high-training low”:
effect of moderate-altitude acclimatization with low-altitude training
on performance. Journal of Applied Physiology, 83(1), 102–112.
PubMed ID: 9216951 doi:10.1152/jappl.1997.83.1.102
Levine, B.D., & Stray-Gundersen, J. (2005). Point: Positive effects ofintermittent hypoxia (live high:train low) on exercise performance are
mediated primarily by augmented red cell volume. Journal of Applied
Physiology, 99(5), 2053–2055. PubMed ID: 16227463 doi:10.1152/
japplphysiol.00877.2005
Lorenzo, S., Halliwill, J.R., Sawka, M.N., & Minson, C.T. (2010).
Heat acclimation improves exercise performance. Journal of Applied
Physiology, 109(4), 1140–1147. doi:10.1152/japplphysiol.00495.
2010
Lundby, C., & Damsgaard, R. (2006). Exercise performance in hypoxia
after novel erythropoiesis stimulating protein treatment. Scandinavian Journal of Medicine & Science in Sports, 16(1), 35–40. PubMed
ID: 16430679
Lundby, C., & Robach, P. (2016). Does ‘altitude training’ increase
exercise performance in elite athletes? Experimental Physiology,101(7), 783–788. PubMed ID: 27173805 doi:10.1113/EP085579
McCleave, E.L., Slattery, K.M., Dufﬁeld, R., Saunders, P.U., Sharma,
A.P., Crowcroft, S.J., & Coutts, A.J. (2017). Temperate performance

beneﬁts after heat, but not combined heat and hypoxic training.
Medicine & Science in Sports & Exercise, 49(3), 509–517. PubMed
ID: 27787334 doi:10.1249/MSS.0000000000001138
McLean, B.D., Buttifant, D., Gore, C.J., White, K., & Kemp, J. (2013a).
Year-to-year variability in haemoglobin mass response to two altitude
training camps. British Journal of Sports Medicine, 47(Suppl. 1),
i51–i58. doi:10.1136/bjsports-2013-092744
McLean, B.D., Buttifant, D., Gore, C.J., White, K., Liess, C., & Kemp, J.
(2013b). Physiological and performance responses to a preseason
altitude-training camp in elite team-sport athletes. International
Journal of Sports Physiology and Performance, 8(4), 391–399.
doi:10.1123/ijspp.8.4.391
Millet, G.P., Chapman, R.F., Girard, O., & Brocherie, F. (2017). Is
live high-train low altitude training relevant for elite athletes?
Flawed analysis from inaccurate data. British Journal of Sports
Medicine. PubMed ID: 29247024 doi:10.1136/bjsports-2017-098083
Neal, R.A., Corbett, J., Massey, H.C., & Tipton, M.J. (2016a). Effectof short-term heat acclimation with permissive dehydration on thermoregulation and temperate exercise performance. Scandinavian
Journal of Medicine & Science in Sports, 26(8), 875–884.
Neal, R.A., Massey, H.C., Tipton, M.J., Young, J.S., & Corbett, J. (2016b).
Effect of permissive dehydration on induction and decay of heatacclimation, and temperate exercise performance. Frontiers in Physiology, 7, 564. doi:10.3389/fphys.2016.00564
Périard, J.D., Cramer, M.N., Chapman, P.G., Caillaud, C., & Thompson,
M.W. (2011). Cardiovascular strain impairs prolonged self-paced
exercise in the heat. Experimental Physiology, 96(2), 134–144.
PubMed ID: 20851861 doi:10.1113/expphysiol.2010.054213
Périard, J.D., & Racinais, S. (2015). Self-paced exercise in hot and cool
conditions is associated with the maintenance of %VO2peak within anarrow range. Journal of Applied Physiology, 118, 1258–1265.
PubMed ID: 25814635 doi:10.1152/japplphysiol.00084.2015
Périard, J.D., & Racinais, S. (2016). Performance and pacing during cycle
exercise in hyperthermic and hypoxic conditions. Medicine & Sciencein Sports & Exercise, 48(5), 845–853. PubMed ID: 26656777 doi:10.
1249/MSS.0000000000000839
Periard, J.D., Racinais, S., & Sawka, M.N. (2015). Adaptations andmechanisms of human heat acclimation: Applications for competitive
athletes and sports. Scandinavian Journal of Medicine & Science inSports, 25(Suppl. 1), 20–38.
Periard, J.D., Travers, G.J.S., Racinais, S., & Sawka, M.N. (2016).
Cardiovascular adaptations supporting human exercise-heat acclimation. Autonomic Neuroscience, 196, 52–62. PubMed ID: 26905458
doi:10.1016/j.autneu.2016.02.002
Peronnet, F., Thibault, G., & Cousineau, D.L. (1991). A theoreticalanalysis of the effect of altitude on running performance. Journalof Applied Physiology, 70(1), 399–404. PubMed ID: 2010398 doi:10.
1152/jappl.1991.70.1.399
Pethick, W.A., Murray, H.J., McFadyen, P., Brodie, R., Gaul, C.A., &Stellingwerff, T. (2019). Effects of hydration status during heatacclimation on plasma volume and performance. Scandinavian Journal of Medicine & Science in Sports, 29(2), 189–199. doi:10.1111/
sms.13319
Prommer, N., Thoma, S., Quecke, L., Gutekunst, T., Volzke, C.,
Wachsmuth, N., . . . Schmidt, W. (2010). Total hemoglobin massand blood volume of elite Kenyan runners. Medicine & Science inSports & Exercise, 42(4), 791–797. PubMed ID: 19952848 doi:10.
1249/MSS.0b013e3181badd67
Racinais, S., Alonso, J.M., Coutts, A.J., Flouris, A.D., Girard, O.,
Gonzalez-Alonso, J., . . . Periard, J.D. (2015). Consensus recommendations on training and competing in the heat. Scandinavian
Journal of Medicine & Science in Sports, 25(Suppl. 1), 6–19.

IJSNEM Vol. 29, No. 2, 2019

Downloaded by on 04/17/19

Heat and Altitude Training

Robach, P., Calbet, J.A., Thomsen, J.J., Boushel, R., Mollard, P.,
Rasmussen, P., & Lundby, C. (2008). The ergogenic effect ofrecombinant human erythropoietin on VO2max depends on theseverity of arterial hypoxemia. PLoS ONE, 3(8), e2996. PubMed
ID: 18714372 doi:10.1371/journal.pone.0002996
Robertson, E.Y., Saunders, P.U., Pyne, D.B., Aughey, R.J., Anson, J.M.,& Gore, C.J. (2010). Reproducibility of performance changes tosimulated live high/train low altitude. Medicine & Science in Sports &Exercise, 42(2), 394–401. PubMed ID: 19927018 doi:10.1249/MSS.
0b013e3181b34b57
Rusko, H.K., Tikkanen, H.O., & Peltonen, J.E. (2004). Altitude andendurance training. Journal of Sports Sciences, 22(10), 928–944.
PubMed ID: 15768726 doi:10.1080/02640410400005933
Saunders, P.U., Pyne, D.B., & Gore, C.J. (2009a). Endurance training ataltitude. High Altitude Medicine & Biology, 10(2), 135–148. doi:10.
1089/ham.2008.1092
Saunders, P.U., Telford, R.D., Pyne, D.B., Cunningham, R.B., Gore, C.J.,
Hahn, A.G., & Hawley, J.A. (2004). Improved running economy inelite runners after 20 days of simulated moderate-altitude exposure.
Journal of Applied Physiology, 96(3), 931–937. PubMed ID:
14607850 doi:10.1152/japplphysiol.00725.2003
Saunders, P.U., Telford, R.D., Pyne, D.B., Gore, C.J., & Hahn, A.G. (2009b).
Improved race performance in elite middle-distance runners after
cumulative altitude exposure. International Journal of Sports Physiology and Performance, 4(1), 134–138. doi:10.1123/ijspp.4.1.134
Saunders, P.U., Telford, R.D., Pyne, D.B., Hahn, A.G., & Gore, C.J.
(2009c). Improved running economy and increased hemoglobin massin elite runners after extended moderate altitude exposure. Journal of
Science and Medicine in Sport, 12(1), 67–72. doi:10.1016/j.jsams.
2007.08.014
Sawka, M.N., Leon, L.R., Montain, S.J., & Sonna, L.A. (2011). Integrated
physiological mechanisms of exercise performance, adaptation,and maladaptation to heat stress. Comprehensive Physiology, 1(4),
1883–1928. PubMed ID: 23733692 doi:10.1002/cphy.c100082
Scoon, G.S., Hopkins, W.G., Mayhew, S., & Cotter, J.D. (2007). Effect of
post-exercise sauna bathing on the endurance performance of competitive male runners. Journal of Science and Medicine in Sport,
10(4), 259–262. PubMed ID: 16877041 doi:10.1016/j.jsams.2006.
06.009
Sharma, A.P., Saunders, P.U., Garvican-Lewis, L.A., Clark, B., Stanley, J.,
Robertson, E.Y., & Thompson, K.G. (2017). The effect of training at
2100-m altitude on running speed and session rating of perceived
exertion at different intensities in elite middle-distance runners.
International Journal of Sports Physiology and Performance, 12(Suppl. 2), S2147–S2152. PubMed ID: 27736249 doi:10.1123/ijspp.
2016-0402
Sharma, A.P., Saunders, P.U., Garvican-Lewis, L.A., Clark, B., Welvaert,
M., Gore, C.J., & Thompson, K.G. (2019). Improved performance innational-level runners with increased training load at 1600 and 1800 m.

219

International Journal of Sports Physiology and Performance, 14(3),286–295. PubMed ID: 30080440 doi:10.1123/ijspp.2018-0104
Shvartz, E., Shapiro, Y., Magazanik, A., Meroz, A., Birnfeld, H.,
Mechtinger, A., & Shibolet, S. (1977). Heat acclimation, physicalﬁtness, and responses to exercise in temperate and hot environments.
Journal of Applied Physiology: Respiratory, Environmental and Exercise Physiology, 43(4), 678–683. doi:10.1152/jappl.1977.43.4.678
Stanley, J., Halliday, A., D’Auria, S., Buchheit, M., & Leicht, A.S. (2015).
Effect of sauna-based heat acclimation on plasma volume and heart
rate variability. European Journal of Applied Physiology, 115(4),785–794. doi:10.1007/s00421-014-3060-1
Telford, R.D., Kovacic, J.C., Skinner, S.L., Hobbs, J.B., Hahn, A.G., &Cunningham, R.B. (1994). Resting whole blood viscosity of elite
rowers is related to performance. European Journal of Applied
Physiology, 68(6), 470–476. doi:10.1007/BF00599515
Thomas, D.Q., Fernhall, B., Blanpied, P., & Stillwell, K. (1995). Changes
in running economy and mechanics during a submaximal 5-km run.
The Journal of Strength and Conditioning Research, 9(3), 170–175.
Tyler, C.J., Reeve, T., Hodges, G.J., & Cheung, S.S. (2016). The effects ofheat adaptation on physiology, perception and exercise performancein the heat: A meta-analysis. Sports Medicine, 46(11), 1699–1724.
PubMed ID: 27106556 doi:10.1007/s40279-016-0538-5
Wachsmuth, N.B., Volzke, C., Prommer, N., Schmidt-Trucksass, A.,
Frese, F., Spahl, O., . . . Schmidt, W. (2013). The effects of classic
altitude training on hemoglobin mass in swimmers. European
Journal of Applied Physiology, 113(5), 1199–1211. PubMed ID:
23138148 doi:10.1007/s00421-012-2536-0
White, A.C., Salgado, R.M., Astorino, T.A., Loeppky, J.A., Schneider,
S.M., McCormick, J.J., . . . Mermier, C.M. (2016). The effect of 10days of heat acclimation on exercise performance in acute hypobaric
hypoxia (4350 m). Temperature, 3(1), 176–185. doi:10.1080/
23328940.2015.1072659
White, A.C., Salgado, R.M., Schneider, S., Loeppky, J.A., Astorino, T.A.,& Mermier, C.M. (2014). Does heat acclimation improve exercise
capacity at altitude? A cross-tolerance model. International Journalof Sports Medicine, 35(12), 975–981. PubMed ID: 24816886
Woods, A.L., Garvican-Lewis, L.A., Rice, A., & Thompson, K.G.
(2017a). 12 days of altitude exposure at 1800 m does not increase
resting metabolic rate in elite rowers. Applied Physiology, Nutrition,and Metabolism, 42(6), 672–676. doi:10.1139/apnm-2016-0693
Woods, A.L., Sharma, A.P., Garvican-Lewis, L.A., Saunders, P.U., Rice,
A.J., & Thompson, K.G. (2017b). Four weeks of classical altitude
training increases resting metabolic rate in highly trained middledistance runners. International Journal of Sport Nutrition andExercise Metabolism, 27(1), 83–90. doi:10.1123/ijsnem.2016-0116
Zurawlew, M.J., Walsh, N.P., Fortes, M.B., & Potter, C. (2016). Postexercise hot water immersion induces heat acclimation and improves
endurance exercise performance in the heat. Scandinavian Journal of
Medicine & Science in Sports, 26, 745–754. PubMed ID: 26661992

IJSNEM Vol. 29, No. 2, 2019