Exercise as it relates to Disease/Utilising exercise in preventing and treating the onset of sarcopenia

Sarcopenia is defined as atrophy or decay in muscle as a consequence of the process of ageing.[1] After reaching a peak in early adulthood, a progressive loss of muscle begins and increases each year to a point where the loss outweighs the gain. As Sarcopenia progresses, daily living activities and mobility are further impaired by the decrease in muscle mass, accounting for the muscle strength loss. The etiology of sarcopenia is less understood, but several mechanisms have been proposed:

  • Decrease in number of motor unit neurons.
  • Altered hormone release (Growth factors, Agonists) and/ or a tissue tolerance to hormone.
  • Altered Tissue response to nutrients.
  • Diminished physical activity.

Health professionals have stated that to manage sarcopenia is to increase physical activity coupled with adequate nutritional intake.[1]

Prevention edit

Sarcopenia comes about due to old age and the consequences that come with it. As a human enters their fourth decade, there is lower motor unit recruitment; the rate of the protein synthesis declines and important hormones such as Human Growth Hormone is also in decline.[2] There are several ways that an adult can slow the process of sarcopenia and eventually reject the negative effects the disease has on them.

Exercise

Experts and professionals have a wide-ranging view on the best approach to specifically achieve hypertrophy, but evidence supporting the notion that physical activity; most significant being resistance training, as being the most efficient way to maintain muscle mass. Resistance training has shown to increase muscle mass and strength, with the gains made in muscle mass and strength via resistance training far outweighing those of any nutritional supplement alone.[3] On the other hand, aerobic exercise commonly does not result in effecting tissue hypertrophy. Instead endurance athletes enhance storage of fats and carbohydrates within their muscles.[4] The benefits that are provided by resistance training against sarcopenia are attributed to the neuromuscular innervation that the resistance program provides, as well as the muscular hypertrophy. These together replace the progressive muscle loss which sequentially maintains muscular strength.[5] This is achieved physiologically, applying an increased load on the muscular system, and have it adapt to the increased stimuli.[6]

Nutrition

One such way to help counteract the negative effects of sarcopenia by ingesting an adequate diet, such as increasing intake of protein. As our bodies grow older, there is a decrease in the rate of protein synthesis. To keep that rate up, it is recommended that an elderly adult intake around 25-30g of protein per meal to ensure that protein synthesis is still working well.[7] The most effective method of preventing sarcopenia however is regular resistance training. With a higher protein intake and an effective resistance training program, an elderly individual will be able to counter the negative effects of sarcopenia.

Prescription edit

Due to the age of the sufferer, it is unsafe for them to be prescribed a hypertrophy resistance training schedule. Therefore a schedule that has contains high repetitions and a low weight is essential for decreasing the effects of sarcopenia.

  • Exercises should cover all the major muscle groups. Multi-joint exercises are recommended, however should be complimented with single-joint exercises as well.
  • 10-15 repetitions in each set, for a minimum of one set.[8]
  • Resistance training sessions should be performed twice per week for optimal results, however studies have shown that even one day per week can lead to the elderly maintaining strength.[8]

When prescribing a program for the patient, it should be personalised for what their goals are at the outcome of the program. Most important aspect of the program is the form of the participant, correct form must be used the whole way through the exercise otherwise it is rendered ineffective.[8]

Further reading edit

References edit

  1. a b Morley, J. E., 2001. Anorexia, sarcopenia, and aging. Nutrition, 17(8), pp. 660-663.
  2. Hasten, D. L., Pak-Loduca, J., Obert, K. A. & Yarasheski, K. E., 2000. Resistance Exercise Acutely In- creases MHC and Mixed Muscle Protein Synthesis Rates in 78-84 and 23-32 yr olds.. American Journal of Physiology, 278(4), pp. 620-626.
  3. Dreyer, H. C. & Volpi, E., 2005. Role of Protein and Amino Acids in the Pathophysiology and Treatment of Sarcopenia. Journal of American College of Nutrition, 24(2), pp. 140S-145S.
  4. Van Loon, L. & Goodpaster, B., 2006. Increased intramuscular lipid storage in the insulin-resistant and endurance-trained state. Pflugers Archiv: European Journal of Physiology, 451(5), pp. 606-616
  5. Borst, S. E., 2004. Interventions for sarcopenia and muscle weakness in older people. Age Ageing, 33(6), pp. 548-555.
  6. Kumar, V., Abbas, A., Fausto, N. & Aster, J., 2010. Robbins and Cotran Pathologic Basis of Disease. 8th ed. s.l.:Saunders.
  7. Paddon-Jones, D. et al., 2005. Exogenous amino acids stimulate human muscle anabolism without inter- fering with the response to mixed meal ingestion. American Journal of Physiology - Endocrinology and Me- tabolism., 288(4), pp. 761-767.
  8. a b c Vella, C., & Kravitz, L. (n.d.). Sarcopenia: The Mystery of Muscle Loss. Exercise Science at UNM. http://www.unm.edu/~lkravitz/Article%20folder/sarcopenia.html