title: Resistance exercise training improves age-related declines in leg vascular conductance and rejuvenates acute leg blood flow responses to feeding and exercise.
abstract: One manifestation of age-related declines in vascular function is reduced peripheral (limb) blood flow and vascular conduction at rest and in response to vasodilatory stimuli such as exercise and feeding. Since, even in older age, resistance exercise training (RET) represents an efficacious strategy for increasing muscle mass and function, we hypothesized that likewise RET would improve age-related declines in leg blood flow (LBF) and vascular conductance (LVC). We studied three mixed-sex age groups (young: 18-28 yr, n = 14; middle aged: 45-55 yr, n = 20; older: 65-75 yr, n = 17) before and after 20 wk of whole body RET in the postabsorptive state (BASAL) and after unilateral leg extensions (6 × 8 repetitions; 75% 1 repetition maximum) followed by intermittent mixed-nutrient liquid feeds (∼6.5 kJ·kg(-1)·30 min(-1)), which allowed us to discern the acute effects of feeding (nonexercised leg; FED) and exercise plus feeding (exercised leg; FEDEX) on vascular function. We measured LBF using Doppler ultrasound and recorded mean arterial pressure (MAP) to calculate LVC. Our results reveal that although neither age nor RET influenced BASAL LBF, age-related declines in LBF responses to FED were eradicated by RET. Moreover, increases in LBF after FEDEX, which occurred only in young and middle-aged groups before RET (+73 ± 9%, and +90 ± 13%, P < 0.001, respectively), increased in all groups after RET (young +78 ± 10%, middle-aged +96 ± 15%, older +80 ± 19%, P < 0.001). Finally, RET robustly improved LVC under FASTED, FED, and FEDEX conditions in the older group. These data provide novel information that supports the premise that RET represents a valuable strategy to counter age-related impairments in LBF/LVC.
authors: University of Nottingham, School of Graduate Entry Medicine and Health, Derby, UK.
authors: Bethan
authors: B
authors: Phillips
authors: John
authors: J
authors: Williams
authors: Philip
authors: P
authors: Atherton
authors: Kenneth
authors: K
authors: Smith
authors: Wulf
authors: W
authors: Hildebrandt
authors: Debbie
authors: D
authors: Rankin
authors: Paul
authors: P
authors: Greenhaff
authors: Ian
authors: I
authors: Macdonald
authors: Michael J
authors: MJ
authors: Rennie
mesh_terms: D017677:Age Distribution; D000367:Age Factors; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D001808:Blood Vessels / Q000502:physiology*; D001823:Body Composition / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply / Q000502:physiology; D012039:Regional Blood Flow / Q000502:physiology; D055070:Resistance Training / Q000379:methods; D014664:Vasodilation / Q000502:physiology; D055815:Young Adult