The aims of the proposed study are (1) to obtain insight in the relationship between muscle contractile characteristics (i.e. muscular oxidative capacity, muscle fiber size and fiber type) and peak power and endurance performance of trained sprint…
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
geen aandoeningen
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The primary outcome of this study is the peak power and endurance cycling
performance of the cyclist (POpeak during Wingate and VO2-max). These two
outcome measures will be related to muscle contractile characteristics (i.e.
mitochondrial density, myoglobin concentration, capillary density, muscle fiber
size and fiber type).
Secondary outcome
The secondary outcome parameter of this study is peak power and endurance of
the cyclist (POpeak during a vertical jump and POmean during a 15,000m time
trial). These two outcome measures will be related to muscle contractile
characteristics (i.e. mitochondrial density, myoglobin concentration,
capillary density, muscle fiber size and fiber type).
The next secondary outcome measure are the non-invasive measurements of muscle
oxidative metabolism (i.e. TSI, O2Hb and HHb, as measured by Near Infrared
Spectroscopy) and muscle architecture (muscle cross-sectional area as measured
by ultra-sound). These outcome variables are compared to invasive measurements
of oxidative metabolism (i.e. mitochondrial density, myoglobin concentration,
capillary density) and muscle architecture (i.e. fiber size).
The last secondary outcome measure is the remaining parameters of peak power
and endurance performance of the cyclist (POpeak, POmean, time-to-peak and
fatigue index during Wingate, and POpeak, POmean and jump height during
vertical jump, P-VO2-max, POmean and finish time 15,000m time trial). These
outcome measures are related to mechanical gross efficiency, maximal voluntary
knee extension torque and anthropometric, cardio-respiratory, hematological and
endocrine parameters.
Background summary
A major and challenging objective in sports and clinical exercise training is
to improve peak power and endurance capacity concurrently. This applies to many
sports, such as cycling, rowing and speed skating. Since skeletal muscles are
the actuators of movement, sports performance is largely determined by muscle
peak power and maximal sustainable power. However, muscle fiber size, which is
a major determinant of muscle peak power, and muscle fiber oxidative capacity,
which is associated with endurance performance, are generally inversely
related. In addition, the adaptations of these variables are mutually
exclusive. We hypothesize that a high oxygen supply to the core of the muscle
fiber (i.e. high capillary density, myoglobin concentration and/or hematocrit)
are requisite for concurrent increases in muscle fiber size and oxidative
capacity and that performance of elite athletes is related to differences in
these variables. Knowledge of the status of key determinants of muscle peak
power and endurance capacity and knowledge of how these variables can be
measured non-invasively are requisite and important for talent identification
and development of successful training strategies.
Study objective
The aims of the proposed study are (1) to obtain insight in the relationship
between muscle contractile characteristics (i.e. muscular oxidative capacity,
muscle fiber size and fiber type) and peak power and endurance performance of
trained sprint and endurance cyclists, (2) to assess the relationship between
invasive and non-invasive measurements of muscular oxidative capacity and
muscle fiber size and (3) to determine the relationships between cycling
performance and mechanical gross efficiency, maximal knee extension torque and
anthropometrical, cardio-respiratory, hematological and endocrine parameters.
Study design
An observational cross-sectional study in trained cyclists (of different
cycling disciplines) will be performed to assess muscle physiological
parameters (muscular oxidative capacity, muscle fiber size and fiber type)
associated with peak power and endurance performance by invasive as well as
non-invasive measurements. Multiple regression analyses will be performed to
determine the contribution of prime physiological parameters to peak power and
endurance performance.
Study burden and risks
Trained cyclists will be subjected to physical (exercise) tests, harvesting a
muscle biopsy (1 sample) and blood sampling (2 x 8 ml). The burden of
harvesting muscle biopsies and blood sampling is low, as these procedures are
quickly performed with little discomfort afterwards. The risks of the physical
(exercise) measurements are negligible. Burden for the participants is mainly
related to their time investment, since participants are required to visit the
laboratory on four occasions for a total amount of approximately 8 hours. This
outcome of the research project is expected to provide insight in the critical
physiological determinants of peak power and/or endurance cycling performance
and to assess to what extent these determinants can be measured noninvasively.
Van der Boechorstraat 9
Amsterdam 1081 BT
NL
Van der Boechorstraat 9
Amsterdam 1081 BT
NL
Listed location countries
Age
Inclusion criteria
Male, age 18-45 year
Trained track or road cyclists (VO2-max > 55ml/kg/min)
Low risk / healthy: based on the outcome of the anamnesis form
Exclusion criteria
Allergic to local anesthetic
Female
Age < 18 or > 45 year
VO2-max < 55 ml/kg/min
Risk: based on the outcome of the anamnesis form
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL49060.029.14 |