SUBJECTIVE RECOVERY-TIME AFTER EXHAUSTING MUSCULAR-ACTIVITY IN POSTPOLIO AND CONTROL SUBJECTS

The purpose of this study was to determine whether the time to subject ively fully recover after the performance of exhausting muscular exerc ise was greater in unstable postpolio as compared with stable postpoli o or control subjects. Twenty-five unstable (those complaining of decl ining muscle strength) postpolio, 16 stable (those denying declining m uscle strength) postpolio, and 25 control subjects performed an isomet ric contraction of the knee extensor (quadriceps femoris) musculature at 40% of maximal torque until they were no longer able to do so. Five -second maximal effort contractions were made every 30 s through 2 min after the time of failure was reached and then at 1-min intervals thr ough 10 min after failure was reached. Subjects reported the duration of time required to subjectively fully recover from this activity. Cho ices of ''less than 1 day,'' ''1 day,'' ''2 days,'' etc., up to ''grea ter than 2 wk'' were given to the subjects for their response. Analysi s was by nonparametric ANOVA and appropriate post hoc comparison proce dures. Unstable postpolio subjects reported a greater recovery time th an either the stable postpolio or control subjects (mean +/- SD of 2.6 +/- 3.0 days, 0.6 +/- 1.0 days, and 0.7 +/- 1.1 days, respectively, P < 0.05). Thus, the reported recovery time from exhausting isometric m uscular exercise was bound to be greater in unstable postpolio subject s than stable postpolio or control subjects. The cause for this findin g is unknown and requires further investigation.