Differential effects of diminished oestrogen and androgen levels on development of skeletal muscle fibres in hypogonadal mice.

Androgen and oestrogen hormones influence skeletal muscle size and the characteristics of skeletal muscle fibre types. These effects have typically been assessed by producing acute shortages (castration/ovariectomy) or by hormone supplementation. Little evidence exists, however, on how sex hormone shortages affect muscle development from early stages through to adulthood.