The Importance of Resistance Exercise Training to Combat Neuromuscular Aging

Older adults undergoing age-related decrements in muscle health can benefit substantially from resistance exercise training, a potent stimulus for whole muscle and myofiber hypertrophy, neuromuscular performance gains, and improved functional mobility. With the use of advancing technologies, research continues to elucidate the mechanisms of and heterogeneity in adaptations to resistance exercise training beyond differences in exercise prescription. This review highlights the current knowledge in these areas and emphasizes knowledge gaps that require future attention of the field.

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Randomized, four-arm, dose-response clinical trial to optimize resistance exercise training for older adults with age-related muscle atrophy

Experimental Gerontology ◽

10.1016/j.exger.2017.09.018 ◽

2017 ◽

Vol 99 ◽

pp. 98-109 ◽

Cited By ~ 27

Author(s):

Michael J. Stec ◽

Anna Thalacker-Mercer ◽

David L. Mayhew ◽

Neil A. Kelly ◽

S. Craig Tuggle ◽

...

Keyword(s):

Older Adults ◽

Clinical Trial ◽

Exercise Training ◽

Resistance Exercise ◽

Muscle Atrophy ◽

Dose Response ◽

Resistance Exercise Training ◽

Age Related

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Preserved Capacity for Adaptations in Strength and Muscle Regulatory Factors in Elderly in Response to Resistance Exercise Training and Deconditioning

Journal of Clinical Medicine ◽

10.3390/jcm9072188 ◽

2020 ◽

Vol 9 (7) ◽

pp. 2188 ◽

Cited By ~ 1

Author(s):

Andreas Mæchel Fritzen ◽

Frank D. Thøgersen ◽

Khaled Abdul Nasser Qadri ◽

Thomas Krag ◽

Marie-Louise Sveen ◽

...

Keyword(s):

Resistance Training ◽

Muscle Strength ◽

Exercise Training ◽

Resistance Exercise ◽

Muscle Mass ◽

Myogenic Regulatory Factors ◽

Resistance Exercise Training ◽

Regulatory Factors ◽

Age Related ◽

Muscle Regulatory Factors

Aging is related to an inevitable loss of muscle mass and strength. The mechanisms behind age-related loss of muscle tissue are not fully understood but may, among other things, be induced by age-related differences in myogenic regulatory factors. Resistance exercise training and deconditioning offers a model to investigate differences in myogenic regulatory factors that may be important for age-related loss of muscle mass and strength. Nine elderly (82 ± 7 years old) and nine young, healthy persons (22 ± 2 years old) participated in the study. Exercise consisted of six weeks of resistance training of the quadriceps muscle followed by eight weeks of deconditioning. Muscle biopsy samples before and after training and during the deconditioning period were analyzed for MyoD, myogenin, insulin-like growth-factor I receptor, activin receptor IIB, smad2, porin, and citrate synthase. Muscle strength improved with resistance training by 78% (95.0 ± 22.0 kg) in the elderly to a similar extent as in the young participants (83.5%; 178.2 ± 44.2 kg) and returned to baseline in both groups after eight weeks of deconditioning. No difference was seen in expression of muscle regulatory factors between elderly and young in response to exercise training and deconditioning. In conclusion, the capacity to gain muscle strength with resistance exercise training in elderly was not impaired, highlighting this as a potent tool to combat age-related loss of muscle function, possibly due to preserved regulation of myogenic factors in elderly compared with young muscle.

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Effects of dietary protein distribution and resistance exercise training on muscle health in older adults

http://isrctn.com/ ◽

10.1186/isrctn64199452 ◽

2017 ◽

Author(s):

Danielle Thomas ◽

Carolyn Greig

Keyword(s):

Older Adults ◽

Exercise Training ◽

Resistance Exercise ◽

Dietary Protein ◽

Protein Distribution ◽

Resistance Exercise Training ◽

Muscle Health

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Effects of aging and Parkinson’s disease on motor unit remodeling: influence of resistance exercise training

Journal of Applied Physiology ◽

10.1152/japplphysiol.00563.2017 ◽

2018 ◽

Vol 124 (4) ◽

pp. 888-898 ◽

Cited By ~ 8

Author(s):

Neil A. Kelly ◽

Kelley G. Hammond ◽

C. Scott Bickel ◽

Samuel T. Windham ◽

S. Craig Tuggle ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Exercise Training ◽

Neuromuscular Junction ◽

Resistance Exercise ◽

Motor Unit ◽

Type I ◽

Resistance Exercise Training ◽

Age Related ◽

Myofiber Type

Aging muscle atrophy is in part a neurodegenerative process revealed by denervation/reinnervation events leading to motor unit remodeling (i.e., myofiber type grouping). However, this process and its physiological relevance are poorly understood, as is the wide-ranging heterogeneity among aging humans. Here, we attempted to address 1) the relation between myofiber type grouping and molecular regulators of neuromuscular junction (NMJ) stability; 2) the impact of motor unit remodeling on recruitment during submaximal contractions; 3) the prevalence and impact of motor unit remodeling in Parkinson’s disease (PD), an age-related neurodegenerative disease; and 4) the influence of resistance exercise training (RT) on regulators of motor unit remodeling. We compared type I myofiber grouping, molecular regulators of NMJ stability, and the relative motor unit activation (MUA) requirement during a submaximal sit-to-stand task among untrained but otherwise healthy young (YA; 26 yr, n = 27) and older (OA; 66 yr, n = 91) adults and OA with PD (PD; 67 yr, n = 19). We tested the effects of RT on these outcomes in OA and PD. PD displayed more motor unit remodeling, alterations in NMJ stability regulation, and a higher relative MUA requirement than OA, suggesting PD-specific effects. The molecular and physiological outcomes tracked with the severity of type I myofiber grouping. Together these findings suggest that age-related motor unit remodeling, manifested by type I myofiber grouping, 1) reduces MUA efficiency to meet submaximal contraction demand, 2) is associated with disruptions in NMJ stability, 3) is further impacted by PD, and 4) may be improved by RT in severe cases. NEW & NOTEWORTHY Because the physiological consequences of varying amounts of myofiber type grouping are unknown, the current study aims to characterize the molecular and physiological correlates of motor unit remodeling. Furthermore, because exercise training has demonstrated neuromuscular benefits in aged humans and improved innervation status and neuromuscular junction integrity in animals, we provide an exploratory analysis of the effects of high-intensity resistance training on markers of neuromuscular degeneration in both Parkinson’s disease (PD) and age-matched older adults.

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Resistance exercise training improves age-related declines in leg vascular conductance and rejuvenates acute leg blood flow responses to feeding and exercise

Journal of Applied Physiology ◽

10.1152/japplphysiol.01031.2011 ◽

2012 ◽

Vol 112 (3) ◽

pp. 347-353 ◽

Cited By ~ 34

Author(s):

Bethan Phillips ◽

John Williams ◽

Philip Atherton ◽

Kenneth Smith ◽

Wulf Hildebrandt ◽

...

Keyword(s):

Blood Flow ◽

Exercise Training ◽

Resistance Exercise ◽

Vascular Function ◽

Whole Body ◽

Middle Aged ◽

Resistance Exercise Training ◽

Vascular Conductance ◽

Leg Blood Flow ◽

Age Related

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.

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