DHEA boosts muscle build-up from strength training

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The over-65s – both men and women – build up more muscle mass and strength if they take 50 mg DHEA in combination with strength training. A ten-month study done by Dennis Villareal and John Holloszy at Washington University confirms this.

DHEA – full name dehydroepiandrosterone – has little effect on its own, but is capable of converting into bioactive steroid hormones, including the PPAR agonist 7-oxo-DHEA, the female sex hormone estradiol and the male sex hormone testosterone. DHEA is produced in the adrenals but, over the age of 25, production decreases with age. By the time you reach 75 your DHEA level is just 20 percent of what it was when you were 25.

Researchers have been studying the effect of DHEA on muscle loss as a result of aging since the 1990s. Most studies have had negative results. In a French study, for example, subjects in their sixties took 50 mg DHEA daily for a year but this had no effect on muscle strength or mass. [Arch Intern Med. 2003 Mar 24;163(6):720-7.]

Researchers at the University of Pennsylvania came to the same conclusion. [J Womens Health (Larchmt). 2005 Jun;14(5):391-400.]

Endocrinologists at the University of California San Diego gave subjects in their fifties 100 mg DHEA daily for three months. They found that the male subjects lost a little weight and became a little stronger, but saw hardly any change in their female subjects. [Clin Endocrinol (Oxf). 1998 Oct;49(4):421-32.] Better than nothing, but not much to write home about.

The subjects in the studies above did no strength training. In the first six months of the experiment that Villareal and Holloszy published in 2006 the subjects didn’t do any strength training either. Half of the subjects took 50 mg DHEA daily, just before going to bed. The other half took a placebo.

After six months the subjects added strength training to their programme. They trained the largest muscle groups three times a week, doing nine basic exercises including squats, leg-presses, seated-rows and chest-presses. Initially the subjects trained at 65 percent of their 1RM, but increased this within six weeks to 85 percent of their 1RM. They continued to take DHEA or the placebo [Pla].

From the start of the experiment [Base] until the end of the first six months [6 Ms] the DHEA supplementation had no effect. But once the subjects started doing strength training, the DHEA group developed significantly more power on the leg-press and chest-press than the subjects in the placebo group.

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The figure above shows the increase in leg muscle mass. DHEA supplementation had no effect on muscle mass in the first six months of the experiment. During the last four months, when the subjects did strength training as well, the DHEA did boost muscle mass growth.

“The finding of a significant potentiating effect of DHEA on the increase in muscle mass and strength induced by weight training provides the rationale for additional studies specifically designed to elucidate the mechanisms by which DHEA replacement brings about this response”, the researchers write.

DHEA enhances effects of weight training on muscle mass and strength in elderly women and men.

Villareal DT, Holloszy JO.

Source

Division of Geriatrics and Nutritional Science, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA.

Abstract

The plasma levels of dehydroepiandrosterone (DHEA) and its sulfated form (DHEAS) decline approximately 80% between the ages of 25 and 75 yr. Muscle mass and strength also decrease with aging. Published data on the effects of DHEA replacement on muscle mass and strength are conflicting. The goals of this study were to determine whether DHEA replacement increases muscle mass and strength and/or enhances the effects of heavy resistance exercise in elderly women and men. We conducted a randomized, double-blind, placebo-controlled study of the effects of 10 mo of DHEA replacement therapy with the addition of weightlifting exercise training during the last 4 mo of the study (DHEA + exercise group, n = 29; placebo + exercise group, n = 27). DHEA alone for 6 mo did not significantly increase strength or thigh muscle volume. However, DHEA therapy potentiated the effect of 4 mo of weightlifting training on muscle strength, evaluated by means of one-repetition maximum measurement and Cybex dynamometry, and on thigh muscle volume, measured by magnetic resonance imaging. Serum insulin-like growth factor concentration increased in response to DHEA replacement. This study provides evidence that DHEA replacement has the beneficial effect of enhancing the increases in muscle mass and strength induced by heavy resistance exercise in elderly individuals.

PMID: 16787962 [PubMed - indexed for MEDLINE]

Source: http://www.ncbi.nlm.nih.gov/pubmed/16787962

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