Clinical trial NCT04611646: Effects of Heat-suit Training on Biological and Performance Characteristics in Elite Cyclists
Official title: Effects of Heat-suit Training on Training-associated Changes in Hemoglobin Mass, Muscle Characteristics and Endurance Performance in Elite Cyclists
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Heat-suit Endurance Training
Non-heat-suit Endurance Training
Keywords: Cycling
Heat
Hemoglobin mass
Skeletal muscle
Elite cyclists
Endurance performance
Mitochondria
Lead sponsor: Inland Norway University of Applied Sciences
Sponsor class: OTHER
First posted: 2020-11-02
Enrollment: 53
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: The study will be conducted as a five-week intervention. In the heat-suit arm, participants will conduct a 50-minute low-intensity cycling session with heat suit five time a week. In the none-heat-suit arm, participants will conduct similar amounts of low-intensity cycling without heat suit. These training sessions will complement the habitual training of the participants. Participants will be allocated into the two arms in a planned randomized manner. In short, participants will be stratified based on baseline performance levels (VO2max), whereby they will be allocated into the two intervention arms in a manner that ensures similar average performance levels between the two arms.
Primary purpose: TREATMENT

Brief summary: The overall objective of the study is to investigate the effects of five weeks of heat-suit training on training-associated changes in hemoglobin mass, skeletal muscle characteristics and endurance exercise performance in elite cyclists

Detailed description: Endurance exercise performance depends on a range of determinants, including hemoglobin mass in blood and content of respiratory mitochondria in skeletal muscle. Low-intensity training (LIT) with heat exposure may be beneficial for development of these variables. The purpose of this study is to investigate the effects of five weeks of LIT-training with heat suit (five times a week; 50 min per session) on hemoglobin mass and other blood characteristics in elite cyclists (males and females) compared to a non-heat-suit training control group, including subsequent investigation of the retrograde effects of \~one month of training without heat suit. The study will also investigate the effects of heat-suit training on endurance exercise performance/performance determinants and other muscle biological charateristics, and will investigate the basic characteristics of mitochondrial function and abundances in these highly trained athletes. Training sessions with heat suit (or lack thereof) will complement the habitual training routines of the participants.

Eligibility criteria: Inclusion Criteria:

* VO2max \> 65 ml/kg/min (male participants)
* VO2max \> 50 ml/kg/min (female participants)
* \>7 hours of endurance training per week for the 6 months leading up to the study

Primary outcomes:
measure: Hemoglobin mass
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
Secondary outcomes:
measure: Maximal oxygen consumption
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Maximal aerobic power output
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Power output at lactate threshold
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Gross efficiency
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Fractional utilization of VO2max (incremental test)
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Fractional utilization of VO2max (15-minute performance test)
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Sprint performance
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Performance during a 15-minute all-out cycling test
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Performance during a 40-minute all-out cycling test
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Maximal concentric force production
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Gene expression in skeletal muscle
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Mitochondrial respiration in skeletal muscle
timeFrame: Immediately after the intervention (T1)
measure: Mitochondrial content in skeletal muscle
timeFrame: Immediately after the intervention (T1)
measure: Total RNA content in skeletal muscle
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Blood volume
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Plasma volume
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Red blood cell volume
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Hematocrit
timeFrame: Changes from before the intervention (T0) to immediately after the intervention (T1)
measure: Hemoglobin mass
timeFrame: Changes from immediately after the intervention (T1) to one month after the intervention (T2)
measure: Blood volume
timeFrame: Changes from immediately after the intervention (T1) to one month after the intervention (T2)
measure: Plasma volume
timeFrame: Changes from immediately after the intervention (T1) to one month after the intervention (T2)
measure: Red blood cell volume
timeFrame: Changes from immediately after the intervention (T1) to one month after the intervention (T2)
measure: Hematocrit
timeFrame: Changes from immediately after the intervention (T1) to one month after the intervention (T2)
Other outcomes:
measure: Training volume
timeFrame: Throughout study completion (daily), an average of five weeks
measure: Iron intake
timeFrame: Throughout study completion (daily), an average of five weeks
Locations:
city: Lillehammer
country: Norway
facility: Inland Norway University of Applied Sciences
state: Inland Norway
Study officials:
affiliation: Research Administrator
name: Anne S Lofthus
role: STUDY_CHAIR
References: