Abstract
The total anaerobic contribution (AC[La-]+PCr) is a valid and
reliable methodology. However, the active muscle mass plays an important role in
the AC[La-]+PCr determination, which might influence its
reliability. Thus, this study aimed to investigate the effects of two exhaustive
intensities on the reliability of the AC[La-]+PCr during a
one-legged knee extension (1L-KE) exercise. Thirteen physically active males
were submitted to a graded exercise to determine the peak power output (PPO) in
the 1L-KE. Then, two constant-load exercises were conducted to task failure at
100% (TTF100) and 110% (TTF110) of PPO,
and the exercises were repeated on a third day. The blood lactate accumulation
and the oxygen uptake after exercise were used to estimate the anaerobic lactic
and alactic contributions, respectively. Higher values of
AC[La-]+PCr were found after the TTF100
compared to TTF110 (p=0.042). In addition, no significant
differences (p=0.432), low systematic error (80.9 mL), and a
significant ICC (0.71; p=0.004) were found for
AC[La-]+PCr in the TTF100. However, an
elevated coefficient of variation was found (13.7%). In conclusion, we
suggest the use of the exhaustive efforts performed at 100% of the PPO
with the 1L-KE model, but its elevated individual variability must be carefully
considered in future studies.
Key words
high-intensity effort - anaerobic metabolism - MAOD - reliability - performance