Chronic alcohol intake, resistance training, and muscle androgen receptor content

Chronic alcohol intake and resistance training (RT) have opposite effects on muscle physiology.

This study examined the effect of chronic alcohol intake on androgen receptor (AR) content in skeletal muscle to determine whether this effect was influenced by RT.

A total of 48 male Sprague Dawley(R) rats (mass = 456 +/- 1 g; mean +/- SE) were divided into five groups: baseline (N = 8), sedentary + alcohol (Sed-Al) (N = 8), sedentary + normal diet (Sed-Nml) (N = 8), exercise + alcohol (Ex-Al) (N = 12), and exercise + normal diet (Ex-Nml) (N = 12). Exercise groups completed a 6 1/3-wk "squat" RT protocol; alcohol groups received an ethanol-rich (35% caloric content of alcohol) diet throughout the 6 1/3-wk period. Baseline animals were killed at the onset of the 6 1/3-wk training period.

Western blot analysis showed no effect of alcohol or RT on the AR of the extensor digitorum longus. Alcohol significantly reduced AR content of the rectus femoris (P < 0.05) and prevented RT-induced increases in AR content of the soleus.

Chronic alcohol intake appeared to reduce the AR content of the type IIB fiber-predominant rectus femoris, and this reduction was not affected by RT. In the type I-predominant soleus, chronic alcohol intake alone had no effect but seemed to prevent RT-induced increases in AR content.