Age & Testosterone
Ageing males tend to experience subtle progressive losses in muscle mass and strength or medically termed sarcopenia. Current research all point to the most important hormone responsible for manhood, testosterone. The age-related decline in testosterone may lead to androgen deficiency or andropause, the male version of menopause comprised of symptoms such as sexual dysfunction, decreased physical performance, impaired cognition, sarcopenia and bone fractures.
How Testosterone Works
Circulating testosterone levels and the constitutional effects it has varies in each individual. Studies have demonstrated that there is an overall decline in free (bio-available) testosterone levels in adults every year, mainly attributed to an increase in sex hormone binding globulin (SHBG) which functionally inhibits testosterone and its secondary products, after being converted by certain enzymes into dihydrotestosterone (DHT) or oestrogen.
Keep T Levels in Check
Maintaining free testosterone levels through external means (intramuscular administration) has been shown to improve lean muscle mass, strength in healthy males aged 60-75 years. Further studies has also shown that patented combinations of Astaxanthin (AX), a compound from a certain species of algae and Saw Palmetto berry extract (SPLE) have been able to increase testosterone levels by inhibiting the enzymes which convert it to DHT or oestrogen. Whilst medical treatments are available to prevent the age-related loss in testosterone, holistic approaches would also be beneficial and more economical. Muscles contain androgen receptors (AR) which respond to the anabolic effects of testosterone. Expression of AR on muscles is affected by the type of training and nutrition. It has been shown that strength training has been able to increase muscle AR in response to increasing testosterone levels post-workout. Another positive outcome is that there has been no reduction in the muscle’s ability to in up-regulate AR in older men. In another study, protein supplements taken by resistance training males have been able to increase lean muscle mass. Furthermore, supplementation with essential amino acids (EAAs) has been shown to promote higher level of both resting and exercise-induced testosterone.
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