The bilateral deficit can be described as when the sum of two unilateral movements exceeds
the bilateral output. If the sum does not exceed the bilateral output, a bilateral facilitation is
present. Little research has been done in males and females comparison of the bilateral deficit.
The purpose of the current study was therefore to compare the bilateral deficit between sexes
in a 1 repetition maximum (RM) leg press. Twenty participants, ten males and ten females,
were recruited (23.4±2.1 years, 71.2±13.1 kg, 172.2±8.9 cm) and seventeen of them
completed the study. The test consisted of two testing sessions (one unilateral with preferred
leg, and one bilateral session) with seven days in between. The 1 RM was attained within six
attempts, with a three minutes rest between every attempt. The current study showed a
bilateral deficit of males (5.6±4.6%) and a bilateral facilitation of females (0.6±5.9%). There
was a significant difference between sexes of p=0.031 (p<0.05). Previous studies have
examined males and females separately, with different methods and protocols. This study
used the same method and protocol in both sexes. Some suggestions of the mechanisms
behind the deficit have been proposed and may explain the current findings, but further
studies are needed. Future research needs to continue to explore and explain the sex
difference in the bilateral strength deficit.
2015. , 25 p.