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

The dependence of power on aerobic and anaerobic energy metabolism and on force production was studied in maximal leg exercise. National and international level male rowers (n = 9) performed four modified (legs-only) rowing ergometer exercises: a progressive test, 2-min (T2), 12-min (T12) and 6-min (T6) all-out tests. In T2, significant correlations were observed between power in T2 (PT2) and oxygen debt (r = 0.83, P < 0.05) and between PT2 and average force production (Fav) during the last 30 s (r = 0.85, P < 0.05). These parameters explained 93% of the variation in PT2. The highest correlations between power in T6 (PT6) and physiological parameters were as follows: maximal oxygen uptake (VO2 max: r = 0.87, P < 0.01), blood bicarbonate concentration before the test ([HCO3-before]: r = 0.85, P < 0.05) and blood lactate concentration on anaerobic threshold (BLaAnT: r = -0.82, P < 0.05). Together, these parameters explained 92% of the variation in PT6. In T12, the total power (PT12) correlated with power of anaerobic threshold (PAnT: r = 0.95, P < 0.001) and with the highest VO2 value in this test (VO2 peak: r = 0.92, P < 0.001). These two parameters explained 96% of the variation in PT12. The decrease of at least one of the force parameters during each test was taken as a sign of fatigue. The decline in force was compensated for by an increase in stroke rate at the end of T6 and T12 (P < 0.01, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)