How is "Effect of Training on Lower Leg Strength" encoded by the genome?
*This study had been conducted female populations.
Do you exercise regularly? Even low levels of activity affect your health over the long term. Training for strong legs and lean thighs is not only for athletes or men and women who want to look good but also for everyone who wants to be happier and healthier as they age. Aging is naturally associated with a loss of independence, a greater risk of falls, and an increase of chronic illnesses, all of which lead to a decline in quality of life. Therefore, the development of physical capacities is necessary to improve the quality of life and healthy aging.
One gene scientists know helps explain muscle strength and fast-twitch muscle fibers is rs1815739 of the α-actinin 3 gene (ACTN3). The deficiency of ACTN3 in the general population appears to be associated with a decrease in the mass, muscle strength, and fragility that accompanies aging. However, among the older population, the biological effect of this genetic variant is still unclear because the results obtained have not been consistent so far.
To clarify the biological effect of this genetic variant and its association with muscle strength among the older population, researchers analyzed the effect of rs1815739 in the ACTN3 gene on physical condition after a two-year training period in a sample of active women aged over 60 years old. All the women who participated in the study received training from a qualified professional in physical activity and sports. This training consisted of two weekly sessions lasting one hour and was based on elderly physical activity guidelines in all municipalities. All programs included a warm-up based on mobility and cardiorespiratory exercises, followed by endurance, resistance training, and balance training in each session. After receiving 24 months of muscle strengthening training from professionals, adapted tests of the Senior Fitness Test battery were used to evaluate the strength of upper and lower extremities and endurance. The Chair Stand Test was used to register lower extremity strength: i.e., the number of times the participant could sit and stand over 30 seconds. Results revealed that the TT genotype participants showed a favorable effect in tests for leg strength after training compared to the other genotypes. However, a generalized worsening was found for all participants in endurance measured by the meters that the participants can cover walking in a circuit in six minutes (the Six-Minute Walk Test).
Several similar studies that used the same strength test in older women failed to find a relationship with the ACTN3 genotype. Due to contradictory results of the effects of ACTN3 and training, studies continue to review the effects after training and evaluate the characteristics of the participants in terms of the training received, age, sex and lifestyle.
Read more about the study here:
https://pubmed.ncbi.nlm.nih.gov/32075076/
Are you interested in learning more about your genetic tendency to experience the effect of a two-year training program on lower leg strength? You can login to your Genomelink TRAITS to see this new genetic trait.
