Physiology and exercise textbooks report that men have a larger muscle fiber area than women. However, the reason for this reported difference is not known. The textbooks also describe that muscle fiber Cross Sectional Area (CSA) can increase with training and improve physical performance. As the situation for women in sports has changed during the last five decades, it might be interesting to investigate what our general knowledge of physiological differences between men and women are based on. The purpose of this study was to critically analyze the scientific basis for the reported facts in our textbooks regarding the differences in muscle fiber CSA between men and women. What groups are being compared? Due to later development of women´s sports - is it possible to assume that these groups were on a comparable level regarding physical activity and physical performance when the studies were performed?
The reference lists in two textbooks in physiology were used as a basis for information. The studies reviewed for type of groups that were compared. These results were also critically analyzed in relation to the possibilities that women had to train and compete at that time.
18 studies were reviewed, 24 different groups were compared in a total of seven muscle groups. The majority, 12/18 were performed in the 1970´s and 1980’s. Eleven studies included groups without any info regarding physical activity. Many studies that were reviewed assumed that biological factors were the main reason to why men and women differ in muscle fiber area. Possible error factors found in the reviewed studies were that the groups in the research was not comparable in levels of physical activity and that there were few subjects.
Insufficient information regarding physical activity makes it impossible to determine if the study populations were comparable in physical activity levels. Based on the relatively later rate of development in women’s sport during the time of the studies, the difference between genders in the studies might be bigger than they are today.
KEYWORDS: CSA, Difference, Gender, Performance, Athletes
2013. , 15 p.