Scand J Med Sci Sports 2016: : –
doi: 10.1111/sms.12660ª 2016 John Wiley & Sons A/S.
Published by John Wiley & Sons Ltd

Effects of submaximal and supramaximal interval training on
determinants of endurance performance in endurance athletes
M. Paquette1,2, O. Le Blanc1,2, S. J. E. Lucas 3,4, G. Thibault1, D. M. Bailey5,6, P. Brassard1,2
1

Department of Kinesiology, Faculty of Medicine, Universit
e Laval, Quebec, QC, Canada, 2Research Center of the Institut
Universitaire de Cardiologie et de Pneumologie de Quebec, Quebec, QC, Canada, 3School of Sport, Exercise and Rehabilitation
Sciences, University of Birmingham, Birmingham, UK, 4Department of Physiology, University of Otago, Dunedin, New Zealand,
5
Neurovascular Research, Laboratory, Faculty of Life Sciences and Education, University of South Wales, South Wales, UK,
6
Sondes Moleculaires en Biologie, Laboratoire Chimie Provence UMR 6264 CNRS, Universit
e de Provence Marseille, Marseille,
FranceCorresponding author: Patrice Brassard, PhD, Department of Kinesiology, Faculty of Medicine, PEPS – Universit
e Laval, 2300
rue de la Terasse, room 2122, Quebec, QC, Canada GIV OA6. Tel.: 418 656-2131 (5621), Fax: 418-656-4908, E-mail: patrice.
brassard@kin.ulaval.ca
Accepted for publication 19 January 2016

We compared the effects of submaximal andsupramaximal cycling interval training on determinants ofexercise performance in moderately endurance-trained
men. Maximal oxygen consumption (VO2max), peak power
output (Ppeak), and peak and mean anaerobic power were
measured before and after 6 weeks (3 sessions/week) of
submaximal (85% maximal aerobic power [MP], HIIT85,
n = 8) or supramaximal (115% MP, HIIT115, n = 9)interval training to exhaustion in moderately endurancetrained men. High-intensity training volume was 47%
lower in HIIT115 vs HIIT85 (304  77 vs 571  200 min;P < 0.01). Exercise training was generally associated withincreased VO2max (HIIT85: +3.3  3.1 mL/kg/min;
HIIT115: +3.3  3.6 ml/kg/min; Time effect P = 0.002;
Group effect: P = 0.95), Ppeak (HIIT85: +18  9 W;
HIIT115: +16  27 W; Time effect P = 0.045; Groupeffect: P = 0.49), and mean anaerobic power (HIIT85:+0.42  0.69 W/kg; HIIT115: +0.55  0.65 W/kg; Timeeffect P = 0.01; Group effect: P = 0.18). Six weeks ofsubmaximal and supramaximal interval training performed
to exhaustion seems to equally improve VO2max andanaerobic power in endurance-trained men, despite half theaccumulated time spent at the target intensity.

In endurance sports such as cycling, maximal oxygen
consumption (VO2max), endurance capacity, anaerobic fitness, and movement efficiency are important
determinants of endurance performance (Joyner &Coyle, 2008). Evidence strongly suggests that both
high-volume, low-intensity and low-volume, highintensity training (Londeree, 1997; Buchheit &Laursen, 2013) are important in order to optimize
adaptations in endurance athletes (St€oggl & Sperlich,2014). High-intensity training, although representinga smaller proportion of athletes’ training volume, isa critical component in the training of all successful
endurance athletes (Seiler, 2010). High-intensity
training is usually performed using interval training,which involves repeated short-to-long bouts ofrather high-intensity exercise interspersed withrecovery periods (Buchheit & Laursen, 2013). Various high-intensity interval training (HIIT) protocols
are utilized in athletes’ training programs, including
submaximal training (below VO2max), VO2max training, and supramaximal training (superior power out-

put to that produced at VO2max); thus, the optimal
exercise training stimulus remains equivocal.
Submaximal interval training can improve endurance performance in highly endurance-trained
cyclists (Westgarth-Taylor et al., 1997; Kristoffersen
et al., 2014; St€
oggl & Sperlich, 2014). Accumulating
evidence indicates that supramaximal interval training can also increase maximal aerobic capacity inmoderately active adults (Rodas et al., 2000; Gist
et al., 2014; Weston et al., 2014), although the beneficial impact of interval training in that intensity
domain remains ambiguous in athletic men maintaining usual low-intensity base-training (Weston
et al., 2014).
Few studies have directly compared submaximal,
maximal, and supramaximal interval training inendurance-trained athletes (Stepto et al., 1999; Laursen et al., 2002; Esfarjani & Laursen, 2007), andthose that have report equivocal findings. For example, Stepto et al. (1999) reported greatest improvements in cycling endurance performance following

1Paquette et al.
six HIIT sessions over 3 weeks performed at 85%
peak power (Ppeak, i.e., submaximal interval training)and 175% Ppeak (i.e., supramaximal interval training), compared to HIIT performed at 80%, 90%, or
95% Ppeak. In contrast, others report that interval
training at VO2max performed twice a week for 4(Laursen et al., 2002) or 10 weeks (Esfarjani & Laursen, 2007) shows larger beneficial effects on performance and key physiological determinants ofperformance (e.g., VO2max and 3000 m running time)in trained athletes compared to supramaximal interval training at 130% of maximal aerobic speed(Laursen et al., 2002; Esfarjani & Laursen, 2007)
and 175% Ppeak (Laursen et al., 2002; Esfarjani &Laursen, 2007). Furthermore, 6 weeks of supramaximal running interval training (3 sessions/week at
130% 3000-m running speed) provided greater benefits for endurance, sprint, and repeated sprint performance than submaximal interval training (at 3000-m
running speed) in physically active but not endurance-trained individuals (Cicioni-Kolsky et al.,2013). Accordingly, whether submaximal or supramaximal interval training elicits the greatest benefits
in endurance-trained athletes remains uncertain.
Most studies comparing different training intensities usually match sessions based on achieving thesame energy consumption across interventions.
However, Seiler et al. (2013) has suggested thatmatching training regimens on energy consumption
induces different overall effort between interval regimens, with total effort or fatigue being lower whenenergy expenditure is achieved with lower intensity
exercise. Importantly, as pointed out by Seiler et al.
(2013) and Rønnestad et al. (2015), athletes match
their HIIT sessions for overall effort and accumulated fatigue in real life situations, not for total work.
Thus, effort matching appears a more valid way tocompare intensities, as they would be used in realworld settings.
Therefore, the aim of this study was to assess theimpact of effort-matched submaximal and supramaximal interval training on determinants of endurance performance in moderately endurance-trained
adults. We hypothesized that, notwithstanding alower training volume, supramaximal interval training would increase to a greater extent aerobic capacity compared to submaximal interval training. We
also expected an improvement in anaerobic capacity
following supramaximal, but not submaximal interval training.
Methods
Participants
Nineteen moderately endurance-trained men (27  7 years,
72  10 kg), with a training history of 5 to 12 h/week for atleast 2 years, volunteered to participate in this study. Participants2

were road cyclists (n = 9), triathletes (n = 7), mountain bikers(n = 2), and a cross-country skier, who were training
8.4  2.7 h/week in the month before the study, and were taking part in 0 to 2 interval training sessions/week (0.5  0.7
HIIT sessions/week on average). This study was approved by
the local ethics committee and was conducted in accordance
to the principles established in the Declaration of Helsinki,with verbal and written informed consent provided by allparticipants.

Experimental design
Participants reported to the laboratory on four separate occasions over a period of 2 weeks to perform: (a) anthropometricand resting measurements, (b) an incremental cycling test to
determine VO2max and Ppeak, (c) a maximal aerobic power(MP) stepwise intermittent protocol, and (d) a 30-s Wingate
test to assess sprint performance (peak and mean anaerobic
power). Participants were asked to refrain from training for atleast 12 h and to avoid alcohol and caffeine consumption for
24 h before each visit. All sessions were performed in the sameorder for all participants and there was at least 24 h between
testing sessions. After these four preliminary evaluation sessions, participants were matched according to their age andVO2max before one from each pair was randomly assigned to
one of two training groups: submaximal (HIIT85) or supramaximal (HIIT115). By study design, participants in bothgroups had similar age (HIIT85: 26  6 years, HIIT115:
27  6 years), height (HIIT85: 1.77  0.08, HIIT115:
1.78  0.08 m), body mass, % body fat, and VO2max (Tables 1
and 2). The four evaluation sessions were repeated 48–96 h following the end of a 6-week training program (see Fig. 1).

Training interventions
Training consisted of three HIIT sessions per week over a period of 6 weeks, with 48–72 h between sessions. On remaining
days, participants were asked to avoid high-intensity exercise,but to maintain a similar low and/or moderate intensity training volume typically performed prior to the study. The HIIT85
group performed repeated 1- to 7-min effort bouts, dependingon the session, at 85% MP, separated by half the effort timeof active recovery (150 W or 50% MP if MP <300 W) until
exhaustion. The HIIT115 group performed repeated 30-s to 1min effort bouts, depending on the session, at 115% MP, separated by twice the effort time of active recovery (150 W or
50% MP if MP <300 W) until exhaustion. Table 3 outlines
the 18 sessions performed in a randomized order during the
6 weeks by participants from HIIT85 and HIIT115 groups. The
reasons for alternating exercise bout duration from one session to another throughout the 6-week training period in bothgroups were to reduce monotony of exercise training and to
focus on exercise intensity, e.g., 85 vs 115% MP, and not exercise duration. Trainings were performed on Tacx Bushido
trainers (Tacx, Terneuzen, The Netherlands).
HIIT85 and HIIT115 protocols were matched for total effort
rather than for total work, which is closer to what athletes
typically do when performing hard interval sessions at various
intensities (Seiler et al., 2013). Accordingly, a number of repetitions was not specifically prescribed for each participant, butthey rather had to keep alternating effort bouts at either
115% or 85% MP and resting periods until exhaustion,
defined as the inability to complete an effort bout (Table 3).
Session rate of perceived exertion (RPE; 0-10 scale) was
obtained within 10 min after the end of each training session(Foster, 1998). After 3 weeks of training, participants’ MP

Sub- and supramaximal interval training
Table 1. Resting measurements pre- and post-trainingGroup

HIIT85 (n = 8)

Time

Pre

Post

Pre

Post

Group

Time

Interaction

72.1  12.0
13.4  4.9
62.4  10.7

71.7  12.0
12.9  4.0
62.5  10.9

73.1  7.5
11.5  5.0
64.5  5.6

72.6  7.4
11.6  4.1
64.0  5.1

0.84
0.49
0.65

0.16
0.65
0.60

0.85
0.46
0.42

115  1566  756  8112  1063  651  7116  1265  654  8124  1171  852  6

0.27
0.31
0.90

0.37
0.41
0.003

0.09
0.048*
0.10

Body composition
Body mass (kg)%Body fat (%)
Lean mass (kg)Resting hemodynamics
Systolic blood pressure (mmHg)
Diastolic blood pressure (mmHg)
Heart rate (bpm)

HIIT115 (n = 9)

P-values

Values are mean  SD; HIIT85, Submaximal training group; HIIT115, Supramaximal training group; *Significant difference (P < 0.05) BP, blood pressure.

Table 2. Determinants of endurance performance adaptations to the 6-week HIITGroup

HIIT85 (n = 8)

Time

Pre

Post

Pre

Post

Group

Time

Interaction

2.06  0.39
3.54  0.53
381  46
3.99  0.63
56.0  6.0
193  6207  2081  849  11
1.39  0.09

2.24  0.55
3.80  0.51
399  54
4.21  0.63
59.3  4.7
191  7205  32
78  652  91.35  0.10

2.07  0.38
3.48  0.34
397  39
4.01  0.53
55.9  4.0
188  8212  3378  854  101.38  0.10

2.17  0.31
3.77  0.42
413  35
4.19  0.40
59.2  1.1
187  6
222  1868  1254  91.42  0.08

0.90
0.84
0.49
0.99
0.95
0.17
0.35
0.11
0.40
0.51

0.03
0.0001
0.045
0.002
0.002
0.25
0.54
0.004
0.30
0.87

0.55
0.78
0.87
0.75
0.98
0.80
0.34
0.11
0.35
0.10

310  51
10.3  3.8

315  55
13.7  4.1

316  44
11.4  4.1

331  3913.5  5.0

0.64
0.86

0.04
0.002

0.27
0.34

21.5  0.6

20.9  1.0

19.6  1.1

19.4  1.0

0.002

0.06

0.36

15.5  0.8
10.0  0.5

15.9  1.8
10.4  0.5

16.6  0.9
10.3  0.7

16.8  1.2
10.8  0.5

0.09
0.18

0.35
0.01

0.66
0.70

Incremental exercise protocol
VT (L/min)
RCP (L/min)
Ppeak (W)VO2max (L/min)
VO2max (ml/kg/min)
HRmax (bpm)
SBPmax (mmHg)
DBPmax (mmHg)
RRmax (breath/min)
RER
MP testMP (W)TMP (min)Cycling efficiency
GME (%)
Sprint performance
Peak anaerobic power (W/kg)
Mean anaerobic power (W/kg)

HIIT115 (n = 9)

P-values

Values are mean  SD; HIIT85, Submaximal training group; HIIT115, Supramaximal training group; VO2max, maximal oxygen consumption, Ppeak, peak
power output during the ramp exercise protocol, HR, heart rate, RER, respiratory exchange ratio, RR, respiration rate, VT, ventilatory threshold,
RCP, respiratory compensation point, MP, maximal aerobic power, TMP, time to exhaustion in MP test, GME, gross mechanical efficiency; Significant
difference (P < 0.05).

was measured, using the same protocol as in the preliminary
evaluation, to adjust training intensity for the 3 remaining
weeks. Total HIIT volume was calculated for each participant, using the number of repetitions performed and thelength of the effort bouts of every session. Work performed
was also calculated for each training session. Total work
included both effort and recovery bouts, while total HIIT
work included only effort bouts. Calculation did not include
warm-up and cool down, which were similar between groups.

Methodology
Anthropometric measurements and resting
hemodynamics
Stature and body mass were measured in each participant. Lean mass and % body fat were assessed using

bioelectrical impedance (InBody520, Biospace, California, USA). Participants then rested supine for10 min. Heart rate (HR; ECG monitoring) and arterial pressure using photoplethysmography (Wesseling et al., 1993) (Nexfin, Edwards Lifesciences,
Ontario, Canada) were continuously monitored on abeat-by-beat basis during the resting period, and thelast 5 min of recording was averaged and taken as
the baseline.
Maximal oxygen consumption (VO2max)
The maximal rate of oxygen consumption (VO2max)
was determined using an incremental cycling test performed on an electromagnetically braked upright3

Paquette et al.

Fig. 1. Experimental design. V, Visit; HIIT85, Submaximal training group; HIIT115, Supramaximal training group.

cycle ergometer (Corival, Lode, the Netherlands).
The test started with 1 min of unloaded pedaling followed by an incremental ramp protocol (30 W/min)to volitional exhaustion. Expired air was continuously recorded using a breath-by-breath gas analyzer(Breezesuite, MedGraphics Corp., Minnesota, SaintPaul, USA) for determination of VO2, carbon dioxide
production (VCO2), and respiratory exchange ratio(RER: VCO2/VO2). Heart rate (HR) was obtained
from ECG monitoring and arterial pressure was measured at rest and every 2 min during the test using an
automated sphygmomanometer with a headphone
circuit option (Model 412, Quinton Instrument,
Bothell, Washington, USA). Maximal VO2 wasdefined as the highest 30-s averaged VO2, concurrent
with a RER ≥1.15. Peak power (i.e., Ppeak) was thehighest power output achieved during the test andmaximal HR (HRmax), respiratory rate (RRmax), andRER (RERmax) were defined as the highest values
Table 3. Interval training sessions that were randomly performed overthe 6 weeks by HIIT85 and HIIT115 participants

HIIT85 (n = 8)

Maximal aerobic power (MP)Training intensity was set relative to participants’
MP in this study. In order to determine the power
output of the first stage of the MP test, predicted MP(MPP) was calculated from the VO2max reached during the incremental cycling test using the following
equation:VO2 ðmL/minÞ ¼ ðpower output [W]  6kpm/WÞ 2ml/kpm þ 300 ðACSM; 2000Þ
Therefore:

HIIT115 (n = 9)

Duration ofeffort bouts (s)Duration ofrecoverybouts (s)Duration ofeffort bouts (s)Duration ofrecoverybouts (s)

60
60
90
90
120
120
150
150
180
180
240
240
300
300
360
360
420
420

30
30
45
45
60
60
75
75
90
90
120
120
150
150
180
180
210
210

30
30
30
30
30
40
40
40
40
40
50
50
50
50
60
60
60
60

60
60
60
60
60
80
80
80
80
80
100
100
100
100
120
120
120
120

4

recorded during the test. The ventilatory threshold(VT) was manually determined using the V-slope
method (Beaver et al., 1986). The respiratory compensation point (RCP) was determined using the criterion of an increase in ventilatory equivalents for O2
and CO2 concomitant to a decrease in end-tidal partial pressure of CO2 (Wasserman et al., 1999).

MPP ðWÞ ¼ ðVO2max ðmL/minÞ  300Þ=12Participants performed the MP test on the same
cycle ergometer as the incremental cycling test.
After a 10-min warm-up (first 5 min: 50% MPP or
150 W, last 5 min: 5% MPP or 15 W increase inpower output every minute), an intermittent testwith 5-min stages was used (see Fig. 2). Cadence
was freely chosen throughout the test. MP was
defined as the power output of the last completed
stage or the power output of an uncompleted stage,
where VO2 increased by >150 mL/min compared tothe previous completed stage. The accumulated timeof exercise (excluding warm-up and recovery phases)
during the MP test (TMP) was used as an index ofendurance. VO2, HR, and arterial pressure were monitored as previously described during the incremental
cycling test.

Sub- and supramaximal interval training
Statistical analysis

Fig. 2. Maximal aerobic power test protocol. MPP, predicted maximal aerobic power, during warm-up and recovery phases, cycling intensity is determined relative to MPP(if MPP ≤300 W) or in absolute units (if MPP >300 W).

Cycling efficiency
Gross mechanical efficiency (GME, %) was used toassess cycling efficiency. GME was defined as theratio of mechanical work output to energy input(Barbeau et al., 1993), where:
Mechanical work output (kgm)¼ power output (W)  time (sec)  0:102kgm/jand:Energy input (kgm) ¼ VO2 ðL/minÞ  4:838kcal/Lðthermal equivalentÞ  426:4kgm/kcal
For calculation of GME, data were collected during the fifth min of the warm-up during the MP test.
Sprint performance
Peak and mean anaerobic power were assessed using
a 30-s Wingate Anaerobic test. The test was performed on an electronic cycle ergometer (Velotron,
RacerMate, Seattle, Washington, USA). Before thetest, participants performed a 10-min warm-up at
150 W or 50% MP (for participants with a
MP < 300 W) with 5-s non-maximal sprints every
min during the last 5 min. Participants were allowed a2-min resting period before starting the test. The test
was preceded by a 2-s unloaded acceleration. The load
was then set at 9.4% of participants’ body mass, andparticipants were asked to attain a peak power as
quickly as possible and to continue to exercise maximally for the duration of the sprint (30 s), whileremaining seated. Peak anaerobic power (peak power/
body weight) and mean anaerobic power (meanpower/body weight) were calculated.

After confirmation of distribution normality using
Shapiro–Wilk normality tests, between-group differences (training characteristics) were analyzed
using independent samples t-tests. For the remaining variables, between-group differences were analyzed using a two-way (Time: Pre vsPost 9 Group: HIIT85 vs HIIT115) repeated measures analysis of variance (ANOVA). Following aninteraction effect (Time 9 Group), differences werelocated using paired (within groups) and independent (between groups) samples t-tests, with Bonferroni correction. Significance was established at
P < 0.05 and data expressed as mean  standard
deviation.

Results
Participant compliance
Data from one participant in HIIT85 were
removed from analysis due to illness and absence
for more than three training sessions. Data fromone participant in HIIT115 were removed fromanalysis due to excessive fatigue during the training regime. Therefore, eight participants fromHIIT85 and nine participants from HIIT115 completed the study.
Training characteristics
High-intensity training volume was 47% less in
HIIT115 than HIIT85 (19.3  4.7 vs 36.6  14.4 min/session; P = 0.005). Total work performed during
each session was 741  317 kJ for HIIT115 and759  200 kJ for HIIT85 (P = 0.89) when considering
effort and recovery bouts, or 585  260 kJ for
HIIT115 and 421  114 kJ for HIIT85 (P = 0.11)
when considering only effort bouts. Participants fromboth groups attended an average of 16  1 training
sessions during the 6 weeks (HIIT85 vs HIIT115:
P = 0.79). Sessions RPE averaged 9.5  0.3 for
HIIT85 (range: from 8 to 10) and 9.3  0.6 for
HIIT115 (range: from 5 to 10) (P = 0.50).
Anthropometric measurements and resting
hemodynamics
Body composition measures were not affected byeither HIIT training program (Table 1). Resting
HR following both training programs was lowered (interaction, P = 0.10; time effect, P < 0.01);
whereas HIIT training intensity differentially influenced resting DBP and SBP measures, although clear
statistical significance was only observed with DBP(Table 1).

5Paquette et al.
Determinants of exercise performance
Incremental cycling exercise to exhaustion

Irrespective of intensity (all interactions, P > 0.05),
training increased VT, RCP, Ppeak, and VO2max but

decreased maximal DBP (Table 2 and Fig. 3).
The other variables measured during the incremental
test remained unchanged following training(Table 2).

(a)

(b)

(c)

(d)

(e)

Fig. 3. Individual training responses for peak power output (A) VO2max (B: ml/kg/min; C: L/min) and peak (D) and meananaerobic power (E) in participants from HIIT85 and HIIT115 groups. Values are mean  SEM. VO2max, maximal oxygen
consumption.

6

Sub- and supramaximal interval training
Mean aerobic power (MP)

Similar increases in MP and TMP were observed following both HIIT training programs (Table 2).

results suggest that supramaximal interval training
is at least as effective as more traditional submaximal interval training to increase VO2max andendurance performance in moderately trainedmen.

Cycling efficiency

GME for participants in the HIIT85 group was
higher than the HIIT115 group at both pre- and posttraining. While on average GME decreased more in
the HIIT85 than the HIIT115 group following training, this did not reach significance (interaction
P = 0.36) nor did the pooled effect (P = 0.06). Mean
cadence during GME assessment was similar
between evaluation sessions.
Sprint performance

Training increased mean anaerobic power irrespectiveof training intensity, whereas peak anaerobic power
tended to increase following training (Table 2).
Discussion
The primary novel finding associated with the present study was that supramaximal interval training
was equally effective compared to effort-matchedsubmaximal interval training given that identicalimprovements in VO2max and anaerobic power wereobserved despite half the accumulated time spent at
the target intensity.
Submaximal and maximal performance
Results from recent studies suggesting the effectiveness of supramaximal interval training for
improving VO2max and submaximal endurance
capacity (Rodas et al., 2000; Burgomaster et al.,2005; Gist et al., 2014; Weston et al., 2014) raise
the question: is supramaximal HIIT more efficientthan submaximal HIIT in improving submaximaland maximal aerobic performance? Our findings
suggest that supramaximal HIIT is more time-efficient than submaximal HIIT in improving
VO2max, as training at 115% MP for ~19 min/session induced the same improvements in VO2max
as training at 85% MP for ~37 min/session, indicating that an increase in training intensity compensates for the decrease in total work duration.
These results are supported by those of a recent
study (Rønnestad et al., 2015) revealing that
10 weeks of supramaximal interval training (30-swork intervals separated by 15-s recovery for
9.5 min) is superior to effort-matched submaximal
interval training (4 9 5 min work intervals separated by 2.5-min recovery periods) of similar total
training duration on several endurance and performance measurements in trained cyclists. These

Supramaximal performance
Improvements in anaerobic fitness have previously
been associated with enhancements in endurance
performance (Bulbulian et al., 1986; Weston et al.,1997); for example, anaerobic fitness has been foundto predict endurance performance in cross-country
mountain biking (Inoue et al., 2012), cross-country
skiing (Staib et al., 2000), and track endurance
cycling (Craig et al., 1993). Findings from the present study indicate that both submaximal and supramaximal HIIT training can be advantageous forendurance athletes as it increases anaerobic fitness(as characterized by mean anaerobic power during a
30-s cycling sprint).
In the present study, HIIT was not associated with
an improvement in cycling efficiency. Cycling efficiency is related to endurance performance, as
cyclists with a higher efficiency can generate a greater
power output for the same VO2 (Coyle et al., 1992).
GME has been reported to be in the range of 18–
23% (Coyle et al., 1992), which is in line with our
results. Previous studies have shown that HIIT performed at an intensity above onset of blood lactate
accumulation (Hopker et al., 2010) and strength
training (Sunde et al., 2010) can slightly improvecycling efficiency in competitive cyclists. Freely chosen cadence and accumulated fatigue after the training protocol may explain our results, as bothcadence and fatigue alter GME (Chavarren & Calbet, 1999; Millet et al., 2000).
There are some limitations to our study that need
to be addressed. Without a performance test (i.e., atime-trial) it is difficult to state which of the two
training interventions will further improve endurance performance. However, the aim of the present
study was to assess the impact of the two training
intensities on important determinants of endurance
performance and not performance per se. Furthermore, our participants were moderately endurancetrained men and therefore our results cannot necessarily be extended to women, healthy or diseased, or
high-performance athletes. We also acknowledge
that the small sample size of our study is associatedwith interpretive limitations, although a retrospective power analysis revealed that we were adequately
powered to detect main effects with values exceeding
0.8 at P < 0.05 for the main determinants of exercise
performance examined in this study.
In summary, these findings suggest that bothsubmaximal and supramaximal interval training,

7Paquette et al.
performed to exhaustion three times a week for
6 weeks, can equally improve VO2max and anaerobic
power in endurance-trained men despite half theaccumulated time spent at the target intensity. These
results may alternatively imply that submaximal
interval training is just as effective as supramaximal
training to enhance these physiological indices of
performance, while avoiding both physiological andpsychological stress that accompany supramaximal
training programs.
Perspectives
The results of this study provide an answer to a question raised by the growing interest of researchers,coaches, and athletes toward supramaximal interval
training: Is effort-matched submaximal and supramaximal interval training equally efficient in improving determinants of endurance performance inendurance-trained men? It appears that both submaximal and supramaximal interval training, performed to exhaustion three times a week for
6 weeks, can equally improve VO2max and anaerobic
power in these moderately trained athletes. Further

research is needed to assess the impact of long-term
submaximal and supramaximal training as well as
the effect of combining both types of training in thesame period or in consecutive training blocks onendurance performance.
Key words: Aerobic capacity, sprint performance,
endurance training, cycling.

Acknowledgements
We express our gratitude to the participants for their
enthusiastic participation during the vigorous exercise training protocol. We also thank Dr. Francßois Billaut for external review, Louis-Charles B. Lacroix and Andree-AnneClement for their assistance in the supervision of training
sessions, and Sophie Castonguay-Paradis for her help indata collection. We also acknowledge Tacx Canada andCycle Lambert for the loan of Tacx Bushido home trainers.
The present study was funded by the Ministere de l’Education, du Loisir et du Sport du Quebec, and the ResearchCenter of the Institut universitaire de cardiologie et depneumologie de Quebec. Myriam Paquette received a scholarship from the Canadian Institutes of Health Research.
Patrice Brassard is a Junior 1 Research Scholar of theFonds de recherche du Quebec – Sante.

References
ACSM. ACMS’s guidelines for exercise
testing and prescription. 6 ed.
Michigan: American College ofSports Medicine Series, 2000: 368.
Barbeau P, Serresse O, Boulay MR.
Using maximal and submaximal
aerobic variables to monitor elite
cyclists during a season. Med Sci
Sports Exerc 1993: 25(9):1062–1069.
Beaver WL, Wasserman K, Whipp BJ.
A new method for detecting
anaerobic threshold by gas exchange.
J Appl Physiol 1986: 60(6):2020–2027.
Buchheit M, Laursen PB. Highintensity interval training, solutions
to the programming puzzle: part I:
cardiopulmonary emphasis. Sports
Med 2013: 43(5): 313–338.
Bulbulian R, Wilcox AR, Darabos
BL. Anaerobic contribution to
distance running performance of
trained cross-country athletes. Med
Sci Sports Exerc 1986: 18(1):107–113.
Burgomaster KA, Hughes SC,
Heigenhauser GJ, Bradwell SN,
Gibala MJ. Six sessions of sprintinterval training increases muscle
oxidative potential and cycle
endurance capacity in humans. J
Appl Physiol 2005: 98(6): 1985–1990.
Chavarren J, Calbet JAL. Cycling
efficiency and pedalling frequency in

8road cyclists. Eur J Appl Physiol
1999: 80(6): 555–563.
Cicioni-Kolsky D, Lorenzen C,
Williams MD, Kemp JG. Endurance
and sprint benefits of high-intensity
and supramaximal interval training.
Eur J Sport Sci 2013: 13(3):304–311.
Coyle EF, Sidossis LS, Horowitz JF,
Beltz JD. Cycling efficiency is related
to the percentage of type I muscle
fibers. Med Sci Sports Exerc 1992: 24(7): 782–788.
Craig NP, Norton KI, Bourdon PC,
Woolford SM, Stanef T, Squires B,
Olds TS, Conyers RAJ, Walsh CBV.
Aerobic and anaerobic indicescontributing to track endurance
cycling performance. Eur J Appl
Physiol Occup Physiol 1993: 67(2):150–158.
Esfarjani F, Laursen PB. Manipulating
high-intensity interval training:
effects on VO2max, the lactate
threshold and 3000 m running
performance in moderately trained
males. J Sci Med Sport 2007: 10(1):27–35.
Foster C. Monitoring training inathletes with reference toovertraining syndrome. Med Sci
Sports Exerc 1998: 30(7): 1164–1168.
Gist NH, Fedewa MV, Dishman RK,
Cureton KJ. Sprint interval training
effects on aerobic capacity: asystematic review and meta-analysis.
Sports Med 2014: 44(2): 269–279.
Hopker J, Coleman D, Passfield L,
Wiles J. The effect of training
volume and intensity on competitive
cyclists’ efficiency. Appl Physiol Nutr
Metab 2010: 35(1): 17–22.
Inoue A, Filho AS, Mello FC, Santos
TM. Relationship between anaerobic
cycling tests and mountain bike crosscountry performance. J Strenght
Cond Res 2012: 26(6): 1589–1593.
Joyner MJ, Coyle EF. Endurance
exercise performance: the physiology
of champions. J Physiol 2008: 586(1):35–44.
Kristoffersen M, Gundersen H, Leirdal
S, Iversen VV. Low cadence interval
training at moderate intensity does
not improve cycling performance inhighly trained veteran cyclists. Front
Physiol 2014: 5: 34.
Laursen PB, Shing CM, Peake JM,
Coombes JS, Jenkins DG. Interval
training program optimization inhighly trained endurance cyclists.
Med Sci Sports Exerc 2002: 34(11):1801–1807.
Londeree BR. Effect of training onlactate/ventilatory thresholds: ameta-analysis. Med Sci Sports Exerc
1997: 29(6): 837–843.
Millet G, Lepers R, Lattier G, Martin
V, Babault R, Maffiuletti N.
Influence of ultra-long-term fatigue

Sub- and supramaximal interval training
on the oxygen cost of two types oflocomotion. Eur J Appl Physiol
2000: 83(4–5): 376–380.
Rodas G, Ventura JL, Cadefau J,
Cuss
o R, Parra J. A short training
programme for the rapid
improvement of both aerobic
and anaerobic metabolism. Eur J
Appl Physiol 2000: 82(5–6):
480–486.
Rønnestad BR, Hansen J, Vegge G,
Tønnessen E, Slettalokken G. Shortintervals induce superior training
adaptations compared with longintervals in cyclists – an effortmatched approach. Scand J Med Sci
Sports 2015: 25: 143–151.
Seiler S. What is best practice fortraining intensity and duration
distribution in endurance athletes?
Int J Sports Physiol Perform 2010: 5(3): 276–291.
Seiler S, Jøranson K, Olesen ND,
Hetlelid KJ. Adaptations to aerobic
interval training: interactive effects ofexercise intensity and total work
duration. Scand J Med Sci Sports
2013: 23: 74–83.

Staib JL, Im J, Caldwell Z, Rundell
KW. Cross-country ski racing
performance predicted by aerobic
and anaerobic double poling power.
J Strenght Cond Res 2000: 14(3):282–288.
Stepto NK, Hawley JA, Dennis SC,
Hopkins WG. Effects of different
interval-training programs on cycling
time-trial performance. Med Sci
Sports Exerc 1999: 31(5): 736–741.
St€
oggl T, Sperlich B. Polarized training
has greater impact on key endurance
variables than threshold, highintensity, or high volume training.
Front Physiol 2014: 5: 33.
Sunde A, Støren O, Bjerkaas M,
Larsen MH, Hoff J, Helgerud J.
Maximal strenght training improves
cycling economy in competitive
cyclists. J Strenght Cond Res 2010:24(8): 2157–2165.
Wasserman K, Hansen JE, Sue DY,
Casaburi R, Whipp BJ. Physiology
of exercise. In: Principles of exercise
testing and interpretation. 3rd edn.
Philadelphia: Lippincott Williams &Wilkins, 1999: 30–32.

Wesseling KH, Jansen JRC, Settels JJ,
Schreuder JJ. Computation of aortic
flow from pressure in humans using
a non-linear, three-element model.
J Appl Physiol 1993: 74(5): 2566–
2573.
Westgarth-Taylor C, Hawley JA,
Ricard MD, Myburgh KH, Noakes
TD, Dennis SC. Metabolic andperformance adaptations to interval
training in endurance-trained cyclists.
Eur J Appl Physiol 1997: 75(4): 298–
304.
Weston AR, Myburgh KH, Lindsay
FH, Dennis SC, Noakes TD,
Hawley JA. Skeletal muscle
buffering capacity and endurance
performance after high-intensity
interval training by well-trained
cyclists. Eur J Physiol Occup
Physiol 1997: 75(1): 7–13.
Weston M, Taylor KL, Batterham
AM, Hopkins WG. Effects of lowvolume high-intensity interval
training (HIT) on fitness in adults: ameta-analysis of controlled and noncontrolled trials. Sports Med 2014:
44(7): 1005–1017.

9