Faculty Opinions recommendation of Lifelong strength training mitigates the age-related decline in efferent drive.

Abstract Strength training performed with heavy loads and maximal intended velocity is documented to enhance efferent neural drive to maximally contracting musculature in older adults. However, it remains unclear whether the neural plasticity following training result from motor skill learning or if external resistance is a prerequisite. To investigate this, we assessed electrically evoked potentials (H-reflex and V-waves normalized to maximal M-wave) and voluntary activation (VA) in 36 older adults (73 ± 4 years) randomized to 3 weeks of plantar flexion strength training, with (maximal strength training [MST]) or without (unloaded ballistic training [UBT]) heavy external loading (90% of one repetition maximum), or a control group. Both training groups aimed to execute the concentric phase of movement as fast and forcefully as possible. The MST group improved maximal voluntary contraction (MVC) and rate of force development (RFD) by 18% ± 13% (p = .001; Hedges g = 0.66) and 35% ± 17% (p < .001; g = 0.94), respectively, and this was different (MVC: p = .013; RFD: p = .001) from the UBT group which exhibited a 7% ± 8% (p = .033; g = 0.32) increase in MVC and a tendency to increase RFD (p = .119; g = 0.22). Concomitant improvements in efferent neural drive (Vmax/Msup ratio: 0.14 ± 0.08 to 0.24 ± 0.20; p = .010) and a tendency towards increased VA (79% ± 9% to 84% ± 5%; p = .098), were only apparent after MST. No changes were observed in Hmax/Mmax ratio for the groups. In conclusion, external loading during exercise training appears to be a prerequisite for efferent neural drive enhancement in older adults. Thus, strength training with heavy loads should be recommended to counteract the typically observed age-related decline in motoneuron firing frequency and recruitment.

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Lifelong strength training mitigates the age-related decline in efferent drive

Journal of Applied Physiology ◽

10.1152/japplphysiol.00117.2016 ◽

2016 ◽

Vol 121 (2) ◽

pp. 415-423 ◽

Cited By ~ 15

Author(s):

Runar Unhjem ◽

Mona Nygård ◽

Lene T. van den Hoven ◽

Simranjit K. Sidhu ◽

Jan Hoff ◽

...

Keyword(s):

Strength Training ◽

Plantar Flexion ◽

H Reflex ◽

Voluntary Activation ◽

M Wave ◽

Reflex Amplitude ◽

Age Related ◽

Musculus Soleus ◽

V Wave ◽

Voluntary Contractions

Recently, we documented age-related attenuation of efferent drive to contracting skeletal muscle. It remains elusive if this indication of reduced muscle strength is present with lifelong strength training. For this purpose, we examined evoked potentials in the calf muscles of 11 [71 ± 4 (SD) yr] strength-trained master athletes (MA) contrasted with 10 (71 ± 4 yr) sedentary (SO) and 11 (73 ± 6 yr) recreationally active (AO) old subjects, as well as 9 (22 ± 2 yr) young controls. As expected, MA had higher leg press maximal strength (MA, 185 ± 32 kg; AO, 128 ± 15 kg; SO, 106 ± 11 kg; young, 147 ± 22 kg, P < 0.01) and rate of force development (MA, 5,588 ± 2,488 N/s; AO, 2,156 ± 1,100 N/s; SO, 2,011 ± 825 N/s; young, 3,663 ± 1,140 N/s, P < 0.05) than the other groups. MA also exhibited higher musculus soleus normalized V waves during maximal voluntary contractions (MVC) [maximal V wave amplitude/maximal M wave during MVC (Vsup/Msup); 0.28 ± 0.15] than AO (0.13 ± 0.06, P < 0.01) and SO (0.11 ± 0.05, P < 0.01), yet lower than young (0.45 ± 0.12, P < 0.01). No differences were apparent between the old groups in H reflex recorded at rest or during MVC [maximal H reflex amplitude/maximal M wave during rest (Hmax/Mmax); maximal H reflex amplitude during MVC/maximal M wave during MVC (Hsup/Msup)], and all were lower ( P < 0.01) than young. MA (34.4 ± 2.1 ms) had shorter ( P < 0.05) H reflex latency compared with AO (36.4 ± 3.7 ms) and SO (37.3 ± 3.2 ms), but longer ( P < 0.01) than young (30.7 ± 2.0 ms). Using interpolated twitch analysis, MA (89 ± 7%) had plantar flexion voluntary activation similar to young (90 ± 6%), and this was higher ( P < 0.05), or tended to be higher ( P = 0.06–0.09), than SO (83 ± 10%) and AO (84 ± 5%). These observations suggest that lifelong strength training has a protective effect against age-related attenuation of efferent drive. In contrast, no beneficial effect seems to derive from habitual recreational activity, indicating that strength training may be particularly beneficial for counteracting age-related loss of neuromuscular function.

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A Typology of Factors Influencing Seniors’ Participation in Strength Training in Gyms and Fitness Centers

Journal of Aging and Physical Activity ◽

10.1123/japa.2017-0166 ◽

2018 ◽

Vol 26 (3) ◽

pp. 492-498 ◽

Cited By ~ 2

Author(s):

Simone Pettigrew ◽

Elissa Burton ◽

Kaela Farrier ◽

Anne-Marie Hill ◽

Liz Bainbridge ◽

...

Keyword(s):

Older People ◽

Strength Training ◽

Retention Strategies ◽

Fitness Centers ◽

Physical Decline ◽

Stakeholder Groups ◽

Factors Influencing ◽

Age Related ◽

Health Practitioners ◽

Relevant Factors

Older people are less likely to engage in strength training than their younger counterparts, despite the substantial benefits of this form of exercise for preventing and addressing age-related physical decline. In many countries, strength training programs are available for older people yet are undersubscribed. The aim of this study was to identify the factors influencing older people’s participation in strength training at gyms and fitness centers to provide insights into potentially effective recruitment and retention strategies for this population. A total of 79 individuals from four stakeholder groups (seniors, fitness center instructors and managers, health practitioners, and those involved in policy) were interviewed to identify and explicate relevant factors. A detailed typology was developed that provides insights into potential strategies at five ecological system levels: intrapersonal, interpersonal, organizational, social, and policy. The typology can be used as a tool for identifying opportunities to encourage strength training participation among older people.

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Krafttraining im Alter: Hintergründe, Ziele und Umsetzung

Swiss Sports & Exercise Medicine ◽

10.34045/ssem/2014/25 ◽

2014 ◽

Vol 62 (4) ◽

Keyword(s):

Quality Of Life ◽

Older People ◽

Strength Training ◽

Medical Care ◽

Muscle Mass ◽

Balance Training ◽

Therapeutic Effects ◽

Explosive Strength ◽

Age Related

In recent decades, increasingly greying societies have been noticed in industrialized nations. The rise in medical care necessary to manage the health of this aging population will ensue huge financial burdens on the healthcare system. The increase of age-specific diseases, compounded by declines in neuromuscular performance constitute two key reasons for a rise in the medical care of older people. Current scientific knowledge reveals that a consequence of aging is the loss of muscle mass and thus, a decrease in maximum and explosive strength. The strength loss and impaired static and dynamic postural control collectively lead to the increased frequency of falls, often leading to serious ramifications which are further augmented by the loss of autonomy and a decline in quality of life. A combined strength and balance training program is to counteract age-related degradation processes and thereby maintain mobility, autonomy and quality of life longer. Humans are able to engage in physical training lifelong. An age-appropriate strength training protocol can counteract the loss of muscle mass and the reduction of both maximum and explosive strength. Likewise, research indicates that strength training elicits preventive and therapeutic effects on osteoporosis, diabetes type 2 and other chronic diseases. Training programs should predominantly counteract the physical deficits of older people. Reducing the risk of falling and maintaining autonomy as long as possible are imperative training goals. The literature suggests that autonomous people aged 65 to 97 can reduce the frequency of falls by a range of 15–50% simply by executing strength and balance training regularly. These figures testify to the immense preventive potential of physical activity in older people.

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Benefits of Strength Training for Elderly Women // Dobrobiti treninga snage za žene treće životne dobi

Спортске науке и здравље - АПЕИРОН ◽

10.7251/ssh1702077s ◽

2018 ◽

Vol 14 (2) ◽

Author(s):

Marko DM Stojanović ◽

Patrik Drid ◽

Dejan Madić ◽

Sergej M Ostojić

Keyword(s):

Muscle Strength ◽

Strength Training ◽

Muscle Power ◽

Elderly Women ◽

Functional Performance ◽

Signs And Symptoms ◽

Related Phenomenon ◽

Age Related ◽

Muscle Attenuation ◽

Force Time

The aging process is associated with loss of skeletal muscle mass and increase in intramuscular fat, the latter also defined as muscle attenuation. Muscle weakness, termed sarcopenia and dynapenia, is a normal age-related phenomenon, occurring at a rate of 1% to 5% annually from the age of 30. This rate means that given typical patterns of physical activity, a 70-year-old woman could have 50% to 70% less strength than she had at age 30. Contrary to long held beliefs, the muscles of elderly women (i.e. aged 65 years and older) continue to be adaptable, even into the extremes of old age, particularly if their muscles are significantly overloaded during training. Therefore, effective strengthening practices must be employed to maintain the highest level of function and achieve optimal aging in elderly women. Done regularly (2-3 times a week), strength training preserve bone density, independence and vitality with age. In addition, strength training also has the ability to reduce the risk of osteoporosis and the signs and symptoms of numerous chronic diseases such as heart disease, arthritis and type 2 diabetes, while also improving sleep and reducing depression. Finally, though muscle strength has been recognized as an important predictor for reduced functional performance, emerging evidence suggests that muscle power (the product of force time velocity or the rate of performing work) is highly effective to elicit substantial improvements in maximal mechanical muscle function (rapid force generation, muscle power and muscle strength) and in functional performance in old and very old women.

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Morphological and biochemical changes in old rat muscles: effect of increased use

Journal of Applied Physiology ◽

10.1152/jappl.1989.67.4.1409 ◽

1989 ◽

Vol 67 (4) ◽

pp. 1409-1417 ◽

Cited By ~ 49

Author(s):

H. Klitgaard ◽

A. Brunet ◽

B. Maton ◽

C. Lamaziere ◽

C. Lesty ◽

...

Keyword(s):

Strength Training ◽

Fiber Type ◽

Recruitment Pattern ◽

Lateral Gastrocnemius ◽

Metabolic Characteristics ◽

Age Related ◽

Male Wistar Rats ◽

Fiber Type Distribution ◽

Induced Changes ◽

Skeletal Muscle Strength

Male Wistar rats were strength and swim trained during a substantial period of old age to determine the influence of aging and activity on the histochemical and metabolic characteristics of a predominantly slow (soleus) and a predominantly fast (plantaris) skeletal muscle. Strength training counteracted the age-related atrophy of the fibers and the age-induced changes in fiber-type distribution of both muscles. Swim training, on the other hand, was without any effect on these parameters. The activity of both mitochondrial and cytoplasmic enzymes became lower with aging in the soleus muscle, whereas only the activity of the cytoplasmic enzymes became lower in the plantaris. Strength training reduced the aerobic capacity of both muscles, whereas swim training had the opposite effect. Aging induced a lower glycogen concentration of the lateral gastrocnemius muscle. This was avoided by swim training. The phosphocreatine and adenosine 5'-triphosphate concentrations were unchanged with aging but became higher with strength training. The activity pattern, therefore, seems to have a considerable influence on the age-related modification of the histochemical and metabolic characteristics of skeletal muscles of the rat. The effect, however, is related to the recruitment pattern of the fiber populations and the form of activity.

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Strength training increases resting metabolic rate and norepinephrine levels in healthy 50- to 65-yr-old men

Journal of Applied Physiology ◽

10.1152/jappl.1994.76.1.133 ◽

1994 ◽

Vol 76 (1) ◽

pp. 133-137 ◽

Cited By ~ 127

Author(s):

R. Pratley ◽

B. Nicklas ◽

M. Rubin ◽

J. Miller ◽

A. Smith ◽

...

Keyword(s):

Metabolic Rate ◽

Strength Training ◽

Training Program ◽

Resting Metabolic Rate ◽

Plasma Concentrations ◽

Fat Free Mass ◽

Plasma Norepinephrine ◽

Older Individuals ◽

Age Related ◽

Before And After

Resting metabolic rate (RMR) decreases with age, largely because of an age-related decline in fat-free mass (FFM). We hypothesized that a strength-training program capable of eliciting increases in FFM would also increase RMR in older individuals. To test this hypothesis, RMR, body composition, and plasma concentrations of certain hormones known to affect RMR were measured before and after a 16-wk heavy-resistance strength-training program in 13 healthy men 50–65 yr of age. Average strength levels, assessed by the three-repetition maximum test, increased 40% with training (P < 0.001). Body weight did not change, but body fat decreased (25.6 +/- 1.5 vs. 23.7 +/- 1.7%; P < 0.001) and FFM increased (60.6 +/- 2.2 vs. 62.2 +/- 2.1 kg; P < 0.01). RMR, measured by indirect calorimetry, increased 7.7% with strength training (6,449 +/- 217 vs. 6,998 +/- 226 kJ/24 h; P < 0.01). This increase remained significant even when RMR was expressed per kilogram of FFM. Strength training increased arterialized plasma norepinephrine levels 36% (1.1 +/- 0.1 vs. 1.5 +/- 0.1 nmol/l; P < 0.01) but did not change fasting glucose, insulin, or thyroid hormone levels. These results indicate that a heavy-resistance strength-training program increases RMR in healthy older men, perhaps by increasing FFM and sympathetic nervous system activity.

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Efectos de la velocidad de entrenamiento en fuerza sobre diversas manifestaciones de la fuerza en mujeres adultas mayores (Effect of the velocity resistance training on various manifestations of resistance in older women)

Retos ◽

10.47197/retos.v38i38.73917 ◽

2020 ◽

pp. 325-332

Author(s):

Jairo Alejandro Fernandez Ortega ◽

Luz Amelia Hoyos Cuartas

Keyword(s):

Strength Training ◽

High Speed ◽

Walking Speed ◽

Muscle Power ◽

Functional Performance ◽

Dynamic Equilibrium ◽

Maximum Strength ◽

Lower Limbs ◽

Fitness Test ◽

Age Related

La realización de tareas diarias, como caminar, subir escaleras o levantar objetos, requiere fuerza y potencia muscular. Las reducciones asociadas a la edad en la fuerza y la potencia pueden afectar la capacidad del adulto mayor para llevar a cabo este tipo de actividades. Objetivo: El propósito de este estudio fue examinar los efectos de dos tipos de entrenamiento en fuerza (PEF) de 16 semanas, uno realizado a alta velocidad (GAV), versus uno a baja velocidad (GBV), sobre, la fuerza y potencia máxima muscular, en un grupo de adultas mayores. Metodología: 86 mujeres con edades entre 60-81 años participaron de forma voluntaria en el estudio y fueron asignadas de forma aleatoria al GAV (Tres series a una velocidad de 0.60m/s, con pérdidas máxima del 10% de velocidad) o al GBV. (Tres series de 10 repeticiones al 70% de 1RM) Los grupos realizaron tres entrenamientos semanales. Antes y después del PE se evaluó: la fuerza máxima (1RM), la potencia pico (Pp) y la velocidad media propulsiva (VMP), en extensión en piernas y de brazos, la fuerza prensil, la velocidad de la marcha (VM), y la fuerza resistencia y agilidad (batería senior fitness test). Resultados: después del periodo de entrenamiento se observaron mejoras significativas (p <0.05) en todas las pruebas en los dos grupos. Sin embargo, los resultados obtenidos por el GAV fueron significativamente (p<0.05) superiores a los del GBV, en las pruebas de capacidad funcional, VM, VMP y Pp. En las pruebas de fuerza máxima y fuerza prensil las diferencias no fueron significativas. Conclusión: El entrenamiento en fuerza realizado a altas velocidades parece tener un mejor efecto en el fuerza resistencia y agilidad y en la potencia muscular, que el entrenamiento de fuerza realizado a baja velocidad.Abstract. Performing daily tasks, such as walking, climbing stairs or lifting objects, requires strength and muscular power. Age-related reductions in strength and potency may affect the ability of the elderly to carry out these types of activities. Objective: the purpose of this study was to examine the effects of a sixteen-week strength training program (PE) performed at high speed (GAV) versus a traditionally executed program (GBV), on functional performance, maximum strength, and muscle power in a group of elderly women. Methodology: 86 women aged between 60-81 years old participated voluntarily in the study and were assigned randomly to the GAV (three series at 0.60m/s speed, with maximum losses of 10% speed) or to the GBV (three series with three sets at 70% of 1RM). Both groups performed three weekly training sessions. The maximum strength of upper and lower limbs (1RM), prehensile strength, walking speed, maximum power, mean propulsive velocity (MPV), and functional performance (senior fitness test) were evaluated before and after the PE. Results: significant improvements were observed (p<0.05) in all the tests in the two groups after the twelve weeks of training. However, the results of GAV were significantly (p <0.05) higher than those of GBV regarding agility and dynamic equilibrium, stationary walking, sitting and standing, walking speed over 4 and 6 meters/hour, MPV, and peak power. The differences were not significant in the tests of maximum strength and prehensile force. Conclusion: Strength training performed at high speed seems to have a better effect on functional performance and muscle power than strength training performed at low speed.

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Effects of strength training on muscle power and serum hormones in middle-aged and older men

Journal of Applied Physiology ◽

10.1152/jappl.2001.90.4.1497 ◽

2001 ◽

Vol 90 (4) ◽

pp. 1497-1507 ◽

Cited By ~ 102

Author(s):

M. Izquierdo ◽

K. Häkkinen ◽

J. Ibañez ◽

M. Garrues ◽

A. Antón ◽

...

Keyword(s):

Strength Training ◽

Muscle Power ◽

Older Men ◽

Analysis Of Covariance ◽

Maximal Strength ◽

Middle Aged ◽

Total Strength ◽

Leg Muscles ◽

Age Related ◽

Power Load

Effects of 16-wk strength training on maximal strength and power performance of the arm and leg muscles and serum concentrations [testosterone (T), free testosterone (FT), and cortisol] were examined in 11 middle-aged (M46; 46 ± 2 yr) and 11 older men (M64; 64 ± 2 yr). During the 16-wk training, the relative increases in maximal strength and muscle power output of the arm and leg muscles were significant in both groups ( P < 0.05–0.001), with no significant differences between the two groups. The absolute increases were higher ( P < 0.01–0.05) in M46 than in M64 mainly during the last 8 wk of training. No significant changes were observed for serum T and FT concentrations. Analysis of covariance showed that, during the 16-wk training period, serum FT concentrations tended to decrease in M64 and increase in M46 ( P < 0.05). However, significant correlations between the mean level of individual serum T and FT concentrations and the individual changes in maximal strength were observed in a combined group during the 16-wk training ( r = 0.49 and 0.5, respectively; P < 0.05). These data indicate that a prolonged total strength-training program would lead to large gains in maximal strength and power load characteristics of the upper and lower extremity muscles, but the pattern of maximal and power development seemed to differ between the upper and lower extremities in both groups, possibly limited in magnitude because of neuromuscular and/or age-related endocrine impairments.

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