Interrelations between power, force production and energy metabolism in maximal leg work using a modified rowing...

Area of Science:

• Sports Science
• Exercise Physiology
• Human Performance

Background:

• Understanding the physiological determinants of maximal power output is crucial for optimizing athletic performance.
• Maximal leg exercise in rowing involves complex interactions between aerobic and anaerobic energy systems and force production.

Purpose of the Study:

• To investigate the relationship between power output and aerobic/anaerobic energy metabolism and force production during maximal leg exercise in elite rowers.
• To identify key physiological predictors of power across varying exercise durations (2-min, 6-min, 12-min).

Main Methods:

• Nine elite male rowers performed four maximal leg-only rowing ergometer tests: progressive, 2-min (T2), 6-min (T6), and 12-min (T12) all-out efforts.
• Physiological parameters including oxygen debt, maximal oxygen uptake (VO2 max), blood bicarbonate, and blood lactate were measured.
• Force production and stroke rate were monitored to assess fatigue and compensatory strategies.

Main Results:

• In the 2-min test, power output (PT2) was strongly correlated with oxygen debt and average force production (Fav), explaining 93% of the variation.
• For the 6-min test, maximal oxygen uptake (VO2 max), pre-test blood bicarbonate, and lactate at anaerobic threshold (BLaAnT) were the strongest predictors of power output (PT6), explaining 92% of the variation.
• In the 12-min test, power output (PT12) was highly correlated with anaerobic threshold power (PAnT) and peak oxygen uptake (VO2 peak), explaining 96% of the variation.

Conclusions:

• Aerobic and anaerobic energy systems, alongside force production, are critical determinants of power output in maximal leg exercise.
• The relative importance of these factors shifts with exercise duration, with anaerobic contributions more significant in shorter, intense efforts.
• Rowers employ compensatory strategies, such as increased stroke rate, to maintain power output when force production declines due to fatigue.