To examine whether the effects of casting or immobilisation were similar between the sexes, researchers examined immobilised volunteers for a period of three weeks. While men were able to regain 99 percent of their strength within a week of removing the cast, women’s strength was still 30 percent lower when compared to before the cast was applied.
Ten healthy volunteers completed three weeks of forearm immobilisation (five females and five males, 18 to 29 years of age). The subjects were fitted with a forearm cast on their non-dominant arm and each person’s wrist muscle strength was determined weekly during the immobilisation phase, and a week after the casts were removed. The measurements taken prior to the casting were repeated to detect any gender differences that may have developed over the course of splinting or recovery.
The research team found that men’s strength had returned to baseline levels one week after the cast was removed. Women’s recovery levels, however, were significantly lower, one week after the cast was removed they still exhibited strength deficits of approximately 30 percent below baseline. All the women exhibited a slow recovery of their strength (at least a 15 percent reduction relative to baseline); whereas only one of the men showed a similar deficit.
In explaining possible reasons for the discrepancies, the researchers suggested that hormones, and the role they play in regulating muscle mass, may contribute to slower recovery times in women. Due to the very small sample size, they cautioned against over-interpreting the work and say further research is needed. However, they also stress that when the findings are examined in the context of existing work of others, the result suggests that women may require additional, or more intensive, rehabilitation programmes following periods of immobilisation or bed rest.
MEDICA.de; Source: American Physiological Society (APS)