Individuals with more skeletal muscle tend to be healthier than those with less. Skeletal muscle mass is directly proportional to resting metabolic rate and so those with more lean mass will have higher metabolic rates and are therefore usually leaner. As body fat gain is associated with the development of disease, there is a clear mechanism by which lean muscle mass can confer health benefits. As we age there is a slow decline in lean muscle mass, and this relates to hormonal and lifestyle changes. Activity levels tend to fall and so the stimulatory effect on skeletal muscle protein is lessened and in addition, hormonal changes lessen the anabolism required for the synthesis of new muscle protein. Those who manage to retain more of their lean mass as they age have been shown to have a reduced risk of mortality, and so the current recommendation is to try to attempt to maintain good levels of skeletal muscle mass into old age. In this regard exercise, particularly resistance training, has been shown to be highly beneficial.
Higher protein intakes can be beneficial for a number of reasons. In the case of the elderly, higher protein intakes may facilitate the growth of new skeletal muscle. This is important as skeletal muscle mass is associated with mortality. Higher levels of skeletal muscle can also improve the quality of life by allowing improved strength and flexibility. Maintaining higher levels of skeletal muscle mass into old age may therefore add life to your years and add years to your life.
Evidence also suggests that dietary protein intake is highly important in maintaining skeletal muscle mass. Dietary protein provides amino acids, and these are used to directly build skeletal muscle. As we age we tend to eat less, and this includes a lower protein intake. This can have detrimental effects on the amount of new skeletal muscle that is subsequently synthesised. Studies have investigated the effects of higher intakes of dietary protein on the levels of skeletal muscle in the elderly. Greater protein intakes in the elderly are associated with a higher retention of skeletal muscle mass. However, it is not just the total protein intake that is important. Evidence also suggests that the timing of the protein is also important. An even distribution of protein throughout the day can positively influence the levels of skeletal muscle. Eating greater amounts of protein at each meal spread throughout the day may therefore be the best strategy in order to optimise the synthesis of new skeletal muscle, and this may be of particular benefit to the elderly.
Eat Well, Stay Healthy, Protect Yourself
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