Resistance Training Improves Mental Function

Mild cognitive impairment (MCI) is a condition where a person has minor problems with things like memory, thinking, attention, language or visual depth perception. The problems are usually not severe enough to affect activities of daily living. But some people with MCI go on to develop dementia – Alzheimer’s in particular. A new study published in the Journal of the American Geriatrics Society by Mavros et al from the University of Sydney has looked into the effects of strength training on cognitive function. The researchers selected 100 people with MCI aged 55 or over. Part of the subjects were put through progressive resistance training (PRT) 2x/week for 6 months. Unsurprisingly, the resistance training led to increases in strength but interestingly the strength increases were linked to improvements in mental ability. The researchers conclude that the link between strength gains and cognitive function merits further study.

Lighter Weights Also Help Muscle Growth

Exciting new research by Burd and colleagues shatters currently held beliefs about the type of resistance training required for muscle growth. Their article entitled “Bigger weights may not beget bigger muscles: evidence from acute muscle protein synthetic responses after resistance exercise” has been published in the journal Applied Physiology, Nutrition, and Metabolism. They found that performing repetitions until fatigue (an average of 24 repetitions) with 30% of one repetition maximum (1RM) was just as effective at eliciting muscle protein synthesis (MPS) as 5 repetitions with 90% 1RM! In fact, exercise performed at 30% 1RM produced longer lasting MPS.

The authors believe that maximal muscle fibre recruitment is fundamental in inducing MPS and that lifting light weights to failure causes the fibre activation required. In addition, low-intensity resistance exercise allows for a higher total number of repetitions and greater total exercise volume, which is important in sustaining the MPS response over time.

Burd et al. note that “skeletal muscle mass is a large contributor to daily energy expenditure and will assist in weight management. Additionally, skeletal muscle, because of its overall size, is the primary site of blood glucose disposal and thus will likely play a role in reducing the risk for the development of type II diabetes”.