Age-Related Attenuation of Aerobic Exercise Training Adaptation in 24-Week Old Rats

Studies of age related declines in health and function often focus on the end of the lifespan. However, chronic diseases such as type 2 diabetes (T2D) develop in middle age. The purpose of this study was to determine the effect of aerobic exercise training on vascular and skeletal muscle responses in mature rats. We hypothesized that mature rats would have attenuated adaptations to exercise training. Young (Y; 12-week old; n = 8) and mature (M; 24 week-old; n = 8) male Wistar rats performed 3-weeks of treadmill running (Ex) or remained sedentary (S). After this time period, insulin and glucose were greater in mature compared with young rats (P In summary, mature rats develop insulin resistance and have lower exercise capacity and training adaptation. Vasomotion is impaired and skeletal muscle bioenergetic adaptation to Ex is blunted. As exercise is a cornerstone of therapy for T2D, it is crucial to define the interaction between age and exercise adaptation, and to determine whether T2D modulates or accelerates the impact of age. Future studies will focus on understanding the mechanisms of this age related impairment of exercise adaptation for identification of optimal exercise training and/or pharmacological interventions. Disclosure R.L. Scalzo: None. G.F. Evans: None. S.E. Hull: None. L. Knaub: None. L.A. Walker: None. J.E. Reusch: Research Support; Self; Merck u0026 Co., Inc.. Board Member; Self; American Diabetes Association. Research Support; Self; AstraZeneca. Other Relationship; Self; Sanofi-Aventis.