Clinical trial NCT04637178: Predicting the Efficacy of Resistance Exercise Training for Improving Endurance Performance
Official title: Identifying Molecular Determinants for the Efficacy of Resistance Training for Improving Endurance Performance in Elite Cyclists
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Elite Cyclists
Keywords: Cycling
Endurance performance
Skeletal muscle biology
Individualization
Muscle fiber type proportions
Ribosomal RNA
Lead sponsor: Inland Norway University of Applied Sciences
Sponsor class: OTHER
First posted: 2020-11-19
Enrollment: 25
Sex: ALL
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The overall objective of the study is to identify molecular determinants of the efficacy of resistance training for improving endruance performance in elite cyclists

Detailed description: For elite endurance athletes, the addition of resistance training to habitual endurance training routines generally leads to improved endurance performance. However, this is not always the case, with several individuals failing to respond in the expected manner. This inter-individual variation is likely associated with inherent cellular and molecular charateristics of skeletal muscle. Indeed, responses to resistance training seem to be associated with muscle biological characteristics such as muscle fiber composition and ribosomal content (during the early phase of resistance training).

The study will investigate the association between muscle fibre composition (type I vs type II muscle fiber proportions) / ribosomal content in m. vastus lateralis and the effects of 10 weeks of resistance training on endurance performance in 52 elite cyclists. Half the participants will perform resistance training in addition to their habitual endurance training routines, the other half will perform endurance training-only. Muscle biopsies will be sampled from m. vastus lateralis before and after the first two weeks of the intervention. For muscle fiber composition, the hypothesis is that larger proportions of type II fibers will be associated with more pronounced benefits of resistance training. For ribosomal content, the hypothesis is that higher rRNA content at baseline and larger increases in rRNA content during the initial part of the intervention will be associated with more pronounced benefits of resistance training. No changes are expected in the non-resistance training control group.

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

Exclusion criteria:

- having conducted regular resistance training for the last 6 months leading up to the study

Primary outcomes:
measure: Performance during a 40-minute all-out cycling test
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Performance during a 15-minute all-out cycling test
timeFrame: Changes from before the intervention to immediately after the intervention
Secondary outcomes:
measure: Total RNA in muscle tissue (before intervention)
timeFrame: Before the intervention
measure: Total RNA in muscle tissue (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: Muscle fiber proportions (before intervention)
timeFrame: Before the intervention
measure: Muscle fiber proportions (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: Muscle fiber cross-sectional area (before intervention)
timeFrame: Before the intervention
measure: Muscle fiber cross-sectional area (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: Myonuclear number (before intervention)
timeFrame: Before the intervention
measure: Myonuclear number (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: rRNA expression (before intervention)
timeFrame: Before the intervention
measure: rRNA expression (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: mRNA expression (before intervention)
timeFrame: Before the intervention
measure: mRNA expression (changes after two weeks)
timeFrame: Changes from before the intervention to immediately after the initial two weeks of resistance training
measure: Maximal concentric force production
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Sprint performance
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Maximal oxygen consumption
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Maximal aerobic power output
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Power output at lactate threshold
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Gross efficiency
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Fractional utilization of VO2max (incremental test)
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Fractional utilization of VO2max (15-minute performance test)
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Hemoglobin mass
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Blood volume
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Plasma volume
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Red blood cell volume
timeFrame: Changes from before the intervention to immediately after the intervention
measure: Hematocrit
timeFrame: Changes from before the intervention to immediately after the intervention
Other outcomes:
measure: Endurance training volume
timeFrame: Throughout study completion (daily), an average of ten weeks
measure: Resistance training volume
timeFrame: Throughout study completion (daily), an average of ten 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: