- Resistance training still has effects on older men
- Taking protein around training in older men reduces the usual resultant levels of testosterone in the blood; but
- Taking protein around training did not affect the gene expression associated with other hormonal growth factors.
So in the light of this study and of this one - Protein co-ingestion stimulates muscle protein synthesis during resistance type exercise - is it a good idea to eat protein around your training? I don't know and I can't really comment since I've not tried it, but I can't help thinking that I would throw up.
Androgen receptors and testosterone in men-Effects of protein ingestion, resistance exercise and fiber type.
The purpose of this study was to examine the impact of protein ingestion on circulating testosterone and muscle androgen receptor (AR) as well as on insulin-like growth factor-I (MGF and IGF-IEa) responses to a resistance exercise (RE) bout in (57-72 year) men. Protein (15g whey) (n=9) or placebo (n=9) was consumed before and after a RE bout (5 sets of 10 repetition maximums), and vastus lateralis muscle biopsies were taken pre, 1 and 48h post-RE. The protein ingestion blunted the RE-induced increase in serum free and total testosterone while the RE bout significantly increased muscle AR mRNA levels in older men (P<0.05). However, protein ingestion did not significantly affect AR mRNA or protein expression, or MGF and IGF-IEa mRNA expression at 1 and 48h post-RE. Immunohistochemical staining of muscle cross-sections was done with antibodies specific to AR and MyHC I and II and showed that there seems to be within or near the type-I muscle fibers a greater staining of ARs than within or near the type-II fibres. In conclusion, the protein ingestion hinders RE-induced increase in serum testosterone in older men but may not significantly affect muscle AR, MGF or IGF-IEa gene expression. Furthermore, the present study shows that even older men are able to increase muscle AR mRNA expression in response to a RE bout.