Differential effect of resistance training on the body composition and lipoprotein-lipid profile in older men and women

Traditional and Undulating Periodization on Body Composition, Strength Levels and Physical Fitness in Older Adults

Introduction: Undulating training has been investigated in sedentary and trained adults, but less is known about the influence of undulating training in older adults. Purpose: This study aimed to evaluate body composition, strength levels, and physical fitness in response to traditional or undulating training in older adults. Methods: A controlled, double-arm trial was conducted in eighteen older adults (10 males, 8 females; 64 ± 2.1 years; 165.12 ± 7.5 cm; 72.5 ± 11.4 kg; 26.5 ± 3.2 k·gm⁻²) who were randomly assigned to traditional (n = 9, TT) or undulating training (n = 9, UT) for eight weeks. Dual X-ray absorptiometry was used to measure fat-free mass (FFM), fat mass (FM), and bone mineral density (BMD). Strength levels were evaluated by the handgrip strength and the one-repetition maximum in vertical chest press, rowing machine, squat, monopodal horizontal leg press, and leg extension. In addition, functional capacity was assessed using the Senior Fitness Test (SFT). Statistical analysis included mean/median comparisons to establish the difference after the intervention (paired Student’s t-test or Wilcoxon test), and effect size calculations based on estimates. Results: After correction for fat-free adipose tissue, a significant increase in FFM was observed in both groups, while no significant changes were found in FM and BMD. Upper- and lower-limbs strength showed significant increases in both groups, although clinical significance varied among exercises. Favorable results were seen on the cardiorespiratory fitness and strength components of the SFT in both groups. Conclusions: The 8-week UT and TT protocols are valid options for improving FFM and increasing strength and functional capacity in women and men over 60 years of age.

The effect of regular resistance exercise, vitamin D, and calcium supplements on the gastrocnemius muscle in rats in the post-menopausal period: An experimental study

Background

Menopause is the natural termination of menstruation which affects the quality and important aspects of women's life.

Objective

To evaluate the effect of regular resistance training (Ex) with vitamin D (Vit. D) and calcium (Ca) supplements in the postmenopausal period on muscle tissue in rats.

Materials and Methods

In this experimental study, 72 female Wistar rats (8-10-wk old) were randomly divided into control, placebo, Vit. D, Ca, Ex, Ca + Vit. D, Ex + Ca, Ex + Vit. D, and Ex + Ca + Vit. D groups. Control and placebo groups were fed with a standard diet and sesame oil, respectively. Two month after the ovariectomy, Ex, Ca (35 mg/kg), and Vit. D (10000 IU) were administred in all groups except the control. The number of muscle and inflammatory cells, fiber diameter, endomysium thickness, and degenerative collagen fiber area were assessed through hematoxylin-eosin staining.

Results

Muscle cell number was increased in the Ex + Vit. D + Ca, Vit. D + Ex, and Vit. D groups compared to the control group; also, inflammatory cell number showed significant increase in the Ex + Vit. D + Ca (12 ± 5.46), Vit. D + Ex (14 ± 3.25), Ex (13 ± 4.08), Vit. D (11 ± 3.26), Ca + Vit. D (10 ± 1.01), and Ca + Ex (9 ± 2.87) groups. Muscle fiber diameter in the Ex + Vit. D + Ca and Vit. D + Ex groups was higher than the other groups. Endomysium thickness was significantly decreased in the Ex + Vit. D + Ca and Vit. D + Ex groups compared to the control and placebo groups (p < 0.001). Degenerative collagen fiber area showed a significant increase in the Ex + Vit. D + Ca and Vit. D + Ex groups (p ≤ 0.001) comparison with the control group.

Conclusion

Regular resistance exercise, Vit. D, and Ca supplements can improve muscle morphological features in the postmenopausal period.

Effects of Pyramid Resistance-Training System with Different Repetition Zones on Cardiovascular Risk Factors in Older Women: A Randomized Controlled Trial

This study analyzed the effects of the pyramidal resistance training (RT) system with two repetition zones on cardiovascular risk factors in older women (≥60 years old). Fifty-nine older women were randomly assigned in three groups: non-exercise control (CON, n = 19), narrow-pyramid system (NPR, n = 20), and wide-pyramid system (WPR, n = 20). Training was performed for eight weeks (eight exercises for the whole-body, 3x/week) in which NPR and WPR performed three sets of 12/10/8 and 15/10/5 repetitions, respectively. Regional body fat was estimated by dual-energy X-ray absorptiometry, and blood parameters related to glycemic, lipid, and inflammatory profiles were assessed. After the training period, although no difference was observed for the magnitude of the changes between NPR and WPR, significant group by time interactions indicated benefits with RT compared to CON for reducing body fat (mainly android body fat; −7%) and improving glucose, HDL-C, LDL-C and C-reactive protein (p < 0.05). Composite z-score of cardiovascular risk, created by the average of the intervention effects on the outcomes, indicate similar responses between NPR and WPR, differing from CON (p < 0.001). Results indicate that both the repetition zones of the pyramidal RT reduced similarly the cardiovascular risk in older women.

Resistance Training for Older Adults: Position Statement From the National Strength and Conditioning Association

Fragala, MS, Cadore, EL, Dorgo, S, Izquierdo, M, Kraemer, WJ, Peterson, MD, and Ryan, ED. Resistance training for older adults: position statement from the national strength and conditioning association. J Strength Cond Res 33(8): 2019-2052, 2019-Aging, even in the absence of chronic disease, is associated with a variety of biological changes that can contribute to decreases in skeletal muscle mass, strength, and function. Such losses decrease physiologic resilience and increase vulnerability to catastrophic events. As such, strategies for both prevention and treatment are necessary for the health and well-being of older adults. The purpose of this Position Statement is to provide an overview of the current and relevant literature and provide evidence-based recommendations for resistance training for older adults. As presented in this Position Statement, current research has demonstrated that countering muscle disuse through resistance training is a powerful intervention to combat the loss of muscle strength and muscle mass, physiological vulnerability, and their debilitating consequences on physical functioning, mobility, independence, chronic disease management, psychological well-being, quality of life, and healthy life expectancy. This Position Statement provides evidence to support recommendations for successful resistance training in older adults related to 4 parts: (a) program design variables, (b) physiological adaptations, (c) functional benefits, and (d) considerations for frailty, sarcopenia, and other chronic conditions. The goal of this Position Statement is to a) help foster a more unified and holistic approach to resistance training for older adults, b) promote the health and functional benefits of resistance training for older adults, and c) prevent or minimize fears and other barriers to implementation of resistance training programs for older adults.

Longitudinal comparison of low- and high-velocity resistance training in relation to body composition and functional fitness of older adults

BACKGROUND

Functional mobility disability affects more than one in five adults over 70 years and increases to 80% by 90 years. While negative changes in mobility are multifactorial, deleterious body composition changes contribute significantly. Resistance training alters the negative trajectory of physical function as well as increases lean mass among older adults. Recently, high-velocity (HV) resistance training has been indicated as an effective intervention to increase lean mass and functional performance.

AIMS

The present investigation compared body composition, physical function, and muscular strength changes between HV and LV resistance training programs.

METHODS

Participants > 65 years (n = 53) were randomly assigned to LV, HV, or active control (AC) group and participated in their respective intervention for 48 weeks.

RESULTS

Analysis of covariance revealed no significant body composition changes over time between groups (p > 0.05). Eight-foot up-and-go performance improved in the HV and AC groups (p < 0.05) with no change in the LV group (p > 0.05) over time. Muscular strength increased in both the LV and HV groups within the first 24 weeks, while only in the LV group, muscular strength continued to increase from 24 to 48 weeks (p < 0.05).

DISCUSSION

Resistance training appears to be an effective intervention for improving aspects of physical function and muscular strength; however, no significant changes in body composition were observed over the 48-week intervention.

CONCLUSION

Findings from the current investigation support use of resistance training for improving physical function among community-dwelling older adults.

The effects of 12-week progressive strength training on strength, functional capacity, metabolic biomarkers, and serum hormone concentrations in healthy older women: morning versus evening training

Previous findings suggest that performing strength training (ST) in the evening may provide greater benefit for young individuals. However, this may not be optimal for the older population. The purpose of this study was to compare the effects of a 12-week ST program performed in the morning vs. evening on strength, functional capacity, metabolic biomarker and basal hormone concentrations in older women. Thirty-one healthy older women (66 ± 4 years, 162 ± 4 cm, 75 ± 13 kg) completed the study. Participants trained in the morning (M) (07:30, n = 10), in the evening (E) (18:00, n = 10), or acted as a non-training control group (C) (n = 11). Both intervention groups performed whole-body strength training with 3 sets of 10-12 repetitions with 2-3 minutes rest between sets. All groups were measured before and after the 12-week period with; dynamic leg press and seated-row 6-repetition maximum (6-RM) and functional capacity tests (30-second chair stands and arm curl test, Timed Up and Go), as well as whole-body skeletal muscle mass (SMM) (kg) and fat mass (FM-kg, FM%) assessed by bioelectrical impedance (BIA). Basal blood samples (in the intervention groups only) taken before and after the intervention assessed low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), blood glucose (GLU), triglycerides (TG), high-sensitive C-reactive protein (hsCRP) concentrations and total antioxidant status (TAS) after a 12 h fast. Hormone analysis included prolactin (PRL), progesterone (P) estradiol (ESTR), testosterone (T), follicle stimulating hormone (FSH), and luteinizing hormone (LH). While C showed no changes in any variable, both M and E significantly improved leg press (+ 46 ± 22% and + 21 ± 12%, respectively; p < 0.001) and seated-row (+ 48 ± 21% and + 42 ± 18%, respectively; p < 0.001) 6-RM, as well as all functional capacity outcomes (p < 0.01) due to training. M were the only group to increase muscle mass (+ 3 ± 2%, p < 0.01). Both M and E group significantly (p < 0.05) decreased GLU (-4 ± 6% and -8 ± 10%, respectively), whereas significantly greater decrease was observed in the E compared to the M group (p < 0.05). Only E group significantly decreased TG (-17 ± 25%, p < 0.01), whereas M group increased (+ 15%, p < 0.01). The difference in TG between the groups favored E compared to M group (p < 0.01). These results suggest that short-term "hypertrophic" ST alone mainly improves strength and functional capacity performance, but it influences metabolic and hormonal profile of healthy older women to a lesser extent. In this group of previously untrained older women, time-of-day did not have a major effect on outcome variables, but some evidence suggests that training in the morning may be more beneficial for muscle hypertrophy (i.e. only M significantly increased muscle mass and had larger effect size (M: g = 2 vs. E: g = 0.5).

The Effect of T'ai Chi Exercise on Lipid Profiles: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

BACKGROUND

Cardiovascular disease is a common health problem resulting from many factors, including dyslipidemia. T'ai chi is one of the interventions assigned to improve lipid profiles and other physical outcomes. However, conflicting results might be attributed to different study designs and interventional approaches. A systematic review and meta-analysis are needed to evaluate existing evidence.

OBJECTIVE

The aim of this systematic review and meta-analysis is to evaluate existing randomized clinical trials (RCTs) regarding the overall effect of t'ai chi exercise on lipid profiles.

METHODS

Electronic databases (MEDLINE and Cumulative Index to Nursing and Allied Health Literature) were searched. The authors included only English peer reviewed published RCTs that used a t'ai chi intervention and high-density lipoprotein cholesterol (HDL-C) as the primary outcome along with low-density lipoprotein cholesterol (LDL-C) and/or total cholesterol (TC) as secondary outcomes.

RESULTS

The authors identified 37 potentially eligible studies. Only eight RCTs were eligible for their qualitative review, and seven studies were eligible for meta-analysis. The included studies were rated as having a low risk of bias. Despite the overall low risk of bias, all studies failed to blind participants to group assignment and were generally unclear about whether they were selectively reporting data. A fixed effect model (I² = 38.16%) demonstrated a small positive effect of t'ai chi on HDL-C (Cohen d = 0.12; standard error [SE] = 0.067; p = 0.037). A random effect model demonstrated a medium effect and small effect for LDL-C (Cohen d = 0.47; SE = 0.347; p = 0.089) and TC (Cohen d = 0.34; SE = 0.225; p = 0.066), respectively.

CONCLUSION

T'ai chi may potentially be beneficial on lipid profiles across different age groups and populations. Although there were conflicting results regarding the effect of t'ai chi on lipid profiles, the majority of studies had at least a small positive effect indicating a potential positive effect of t'ai chi on HDL-C, LDL-C, and/or TC. Therefore, further research is needed to confirm the small positive effect of t'ai chi on lipid profiles found in this review.

Effects of testosterone enanthate treatment in conjunction with resistance training on thyroid hormones and lipid profile in male Wistar rats

This study was conducted to determine the effects of 8-week administration of testosterone enanthate (TE) in conjunction with resistance training on thyroid hormones and lipid profiles. Sixty male adult Wistar rats were randomly divided into six groups: C: olive oil, RT: resistance training + olive oil, LD: TE (20 mg/kg), HD: TE (50 mg/kg), RT + LD: RT + TE (20 mg/kg), RT + HD: RT + TE (50 mg/kg). The RT consisted of climbing (5 reps/3 sets) a ladder carrying a load suspended from the tail. At the end, blood specimens were obtained from the orbital sinus and serum concentration of T4, T3, TSH and lipid profiles was determined. The serum concentration of TSH significantly increased in RT + HD group compared to C, and the serum concentration of T4 significantly decreased in LD, HD, RT + LD and RT + HD groups compared to the C and RT groups (p < .05). The concentration of HDL and cholesterol significantly decreased in HD and RT + HD groups compared with C group (p < .05). Both decreased T4 and increased TSH in the RT + HD group likely suggested a primary hypothyroidism as a complication of high-dose administration of testosterone enanthate along with resistance training. Alteration in lipid profile was another complication observed in rats received high doses of testosterone enanthate.

Effect of concurrent resistance and sprint training on body composition and cardiometabolic health indicators in masters cyclists

In older previously sedentary individuals endurance training imposes a more effective stimulus to enhance cardiometabolic health compared with resistance or sprint training. We examined the effect of replacing a portion of endurance training with combined resistance and/or sprint training and how this influences cardiometabolic health indicators in masters endurance cyclists. Twenty-seven well-trained male road cyclists (53.7±8.2 years) were allocated to a resistance and track sprint-cycling training group (RTC, n=10), an endurance and track sprint-cycling group (ETC, n=7) or a control endurance group (CTRL, n=10). Both the RTC and ETC groups completed a 12-week intervention of specific training while the CTRL group maintained their endurance training load. Lower limb lean mass (LLM), trunk fat mass (TFM), fasting blood glucose (FBG), total cholesterol (TC), triglycerides (TG), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured before and after the intervention period. TFM decreased for all groups (P<0.05) while LLM significantly increased for RTC and ETC groups (P<0.05). No significant between group or time effects were observed for FBG, TC, TG, SBP, or DBP. The results suggest that replacing a portion of endurance training with 12 weeks of ETC or RTC training favourably affects body composition by lowering TFM and increasing LLM without negatively affecting cardiometabolic health indicators in well-trained masters endurance cyclists.

Effect of resistance training with elements of stretching on body composition and quality of life in postmenopausal women

INTRODUCTION

Physical activity in elderly persons contributes to prevention and treatment of chronic disease and, through its influence on the musculoskeletal system, increases physical capability and improves mental function.

AIM OF THE STUDY

Aim of the study was to assess the effect of resistance training with elements of stretching on body composition and quality of life in women of postmenopausal age.

MATERIAL AND METHODS

Thirty-eight postmenopausal women aged 62.5 ±5.8 years were randomly divided into two groups. One group participated in an 8-week training program (60 minutes, twice weekly; 4 MET [metabolic equivalent] 2 hours/week). The second group performed no training. A comparison was made of body composition and quality of life (SF-36 Health Survey) prior to and after 8 weeks of training.

RESULTS

In the training group, after 8 weeks there was a significant reduction in body fat (in%; p = 0.028), and an increase in fat-free mass (in%; p = 0.025) and total body water (in%; p = 0.021), which indicates increased muscle mass. Furthermore, there were statistically significant differences in the assessment of quality of life in physical (role-physical [RP], bodily pain [BP], general health [GH] scales; p < 0.005) and mental health (vitality [VT] scale; p = 0.05). In the non-exercising group no changes were observed in features examined in the initial and final test.

CONCLUSIONS

Resistance training with elements of stretching in postmenopausal women improved body composition to achieve a reduction in risk factors associated with excess fatty tissue and muscle mass deficiency. It raises the quality of life in terms of both physical and mental function.

Resistance training improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women

PURPOSE

To examine the effects of resistance training (RT) on metabolic syndrome-related phenotypes in postmenopausal women.

PATIENTS AND METHODS

Twenty-two postmenopausal women (65.0±4.2 years) underwent 12 weeks of whole body progressive training with intensity prescribed based on rating of perceived exertion. Dominant knee extension strength was assessed using an isokinetic dynamometer before and after the intervention. Moreover, all volunteers had blood samples collected for lipid profile, glycemic control, and C-reactive protein analyses. Waist circumference and arterial blood pressure were also measured at baseline and after the training period. Student's t-tests for paired samples and repeated measures ANOVA were used to compare dependent variables, and statistical significance was set at P<0.05.

RESULTS

Isokinetic muscle strength significantly increased (P<0.01) with training. It was observed that waist circumference as well as total and low-density lipoprotein cholesterol levels significantly decreased with training (P<0.01). Total cholesterol/high-density lipoprotein cholesterol ratio, an important marker of cardiovascular disease incidence, was also significantly reduced (from 3.91±0.91 to 3.60±0.74; P<0.01) after the program. Blood glucose, basal insulin, and homeostatic model assessment of insulin resistance were also significantly reduced (P<0.01). No significant alterations were observed for resting blood pressure, triglycerides, or C-reactive protein.

CONCLUSION

Based on the observed results, it can be concluded that a 12-week progressive RT program, besides increasing isokinetic muscle strength, induces beneficial alterations on metabolic syndrome-related phenotypes in postmenopausal women. These findings highlight this mode of exercise as an important component of public health promotion programs for aged women. RT improves isokinetic strength and metabolic syndrome-related phenotypes in postmenopausal women.

Changes in Antioxidant Defense Capability and Lipid Profile after 12-Week Low- Intensity Continuous Training in Both Cigarette and Hookah Smokers: A Follow-Up Study

To examine the impact of low-intensity continuous training program on antioxidant defense capability and lipid profile in male cigarette or hookah smokers. Forty-three male adults participated in a 12-week continuous training program at an intensity of 40% of VO₂max. All subjects were subjected to anthropometric, physical and biochemical tests before and after the training program. The increase of Glutathione reductase (GR) and Superoxide dismutase (SOD) is significant only for cigarette smokers (CS) and hookah smokers (HS) groups. The Malondialdehyde (MDA) decrease and α-tocopherol increase are significant only for HS group. GPx was increased in NS, CS and HS by 2.6% (p< 0.01), 2% (p< 0.05) and 1.7% (p< 0.05) respectively. Likewise, significant improvements of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and TC / HDL-C ratio were observed in three groups. En contrast no significant changes were recorded in triglycerides (TG). Also, significant reduction of total cholesterol (TC) for CS group (p< 0.01) and HS groups (p< 0.05). This continuous training program appears to have an important role in lipid levels improving and oxidative stress attenuation.

The effects of a commercially available botanical supplement on strength, body composition, power output, and hormonal profiles in resistance-trained males

Background

Fenugreek (Trigonella foenum-graecum) is a leguminous, annual plant originating in India and North Africa. In recent years Fenugreek has been touted as an ergogenic aid. The purpose of this study was to evaluate the effects of Fenugreek supplementation on strength and body composition.

Methods

49 Resistance trained men were matched according to body weight and randomly assigned to ingest in a double blind manner capsules containing 500 mg of a placebo (N = 23, 20 ± 1.9 years, 178 ± 6.3 cm, 85 ± 12.7 kg, 17 ± 5.6 %BF) or Fenugreek (N = 26, 21 ± 2.8 years, 178 ± 6 cm, 90 ± 18.2 kg, 19.3 ± 8.4 %BF). Subjects participated in a supervised 4-day per week periodized resistance-training program split into two upper and two lower extremity workouts per week for a total of 8-weeks. At 0, 4, and 8-weeks, subjects underwent hydrodensiometery body composition, 1-RM strength, muscle endurance, and anaerobic capacity testing. Data were analyzed using repeated measures ANOVA and are presented as mean ± SD changes from baseline after 60-days.

Results

No significant differences (p > 0.05) between groups were noted for training volume. Significant group × time interaction effects were observed among groups in changes in body fat (FEN: -2.3 ± 1.4%BF; PL: -0.39 ± 1.6 %BF, p < 0.001), leg press 1-RM (FEN: 84.6 ± 36.2 kg; PL: 48 ± 29.5 kg, p < 0.001), and bench press 1-RM (FEN: 9.1 ± 6.9 kg; PL: 4.3 ± 5.6 kg, p = 0.01). No significant interactions was observed among groups for Wingate power analysis (p = 0.95) or muscular endurance on bench press (p = 0.87) or leg press (p = 0.61). In addition, there were no changes among groups in any clinical safety data including lipid panel, liver function, kidney function, and/or CBC panel (p > 0.05).

Conclusion

It is concluded that 500 mg of this proprietary Fenugreek extraction had a significant impact on both upper- and lower-body strength and body composition in comparison to placebo in a double blind controlled trial. These changes were obtained with no clinical side effects.

Efeitos do treinamento resistido na lipoproteína de baixa densidade

Os benefícios da prática regular do exercício físico estão claramente estabelecidos na literatura. Entretanto, a escolha do tipo de exercício ideal pode ser mais salutar para indivíduos com doenças específicas e patologias associadas. O propósito desta revisão foi verificar se o treinamento resistido (TR) exerce alguma alteração no colesterol da lipoproteína de baixa densidade (LDL-C). Foram observadas grandes diferenças na literatura, dificultando uma conclusão em relação aos benefícios do TR nesta revisão. No entanto, foi visto que o TR pode ser promissor na redução dos níveis de LDL-C, principalmente em homens e mulheres adultos, em pacientes com diabetes mellitus tipo 1 e tipo 2 e em mulheres pré-menopausa, não mostrando diferenças na população idosa. Os autores concluem que o TR é uma boa opção de exercício físico para indivíduos, principalmente quando o treinamento aeróbio (TA) é contraindicado.

Resistance training lowers exercise-induced oxidative stress and homocysteine levels in overweight and obese older adults

OBJECTIVE

To compare exercise-induced oxidative stress and levels of homocysteine and cholesterol in normal-weight and overweight older adults after resistance exercise (RX).

RESEARCH METHODS AND PROCEDURES

This interventional study was conducted at a wellness center. Forty-nine older adults (age range, 60 to 72 years) were stratified by BMI (<25 kg/m(2) normal weight, > or =25 kg/m(2) overweight/obese) and then randomly assigned to either a control non-exercise group or an RX group. The RX group completed a 6-month training program. Exercise-induced lipid hydroperoxides (PEROXs) and thiobarbituric-reactive acid substances, homocysteine, lipoprotein a, cholesterol, and high-density lipoprotein cholesterol were measured before and after the 6-month RX program.

RESULTS

PEROXs and thiobarbituric-reactive acid substances were lower in both the overweight/obese and normal-weight RX-trained groups compared with control groups (p < 0.05). Homocysteine levels were lower in both overweight/obese and normal-weight RX groups compared with control groups (p < 0.05). Lipoprotein a, total cholesterol, and high-density lipoprotein cholesterol were not different in normal-weight and overweight/obese groups before or after RX. The change in muscle strength was correlated with homocysteine at 6 months (r = -0.452, p < 0.05), whereas the change in PEROXs was correlated with the change in body fat (r = -0.329).

DISCUSSION

To our knowledge, these data are the first to show that RX reduces exercise-induced oxidative stress and homocysteine regardless of adiposity, indicating that this protection can be afforded in an older, overweight/obese population as effectively as in healthy older adults. These data suggest that RX may afford some protection against emerging cardiovascular risk factors using a mode of exercise that supports body weight.

Beef and soy-based food supplements differentially affect serum lipoprotein-lipid profiles because of changes in carbohydrate intake and novel nutrient intake ratios in older men who resistive-train

OBJECTIVE

We examined if the predominant source of dietary protein influenced the lipoprotein-lipid profile in older men who performed resistive exercise training (RT).

DESIGN

This is a 14-week, randomized, repeated-measures study with a 12-week period of RT with supplementation of different sources of dietary protein (beef and soy).

SETTING

Nutrition, Metabolism, and Exercise Laboratory, Central Arkansas Veteran's Healthcare System, North Little Rock, Ark. Subjects Twenty-six healthy men were recruited, and 21 men (age 65 +/- 5 years, body mass index 28.2 +/- 2.6 kg/m 2 ) completed the study. Interventions For 14 weeks, all men were counseled to self-select a lacto-ovo-vegetarian diet. For 2 weeks (baseline), all men also consumed 0.6 g-protein/kg per day from portioned quantities of soy-based texturized vegetable protein foods. For the next 12 weeks, 11 men were randomized to continue with texturized vegetable protein foods (VEG group), whereas 10 men were randomized to receive 0.6 g-protein/kg per day from portioned quantities of beef (BEEF group) and continue their otherwise lacto-ovo-vegetarian diet. All men participated in RT 3 d/wk during this 12-week period. Assessments of upper and lower body muscle strength and power, serum lipoprotein-lipid profile, and dietary nutrient intakes were made at baseline and week 12 of RT (POST).

RESULTS

The BEEF and VEG groups increased ( P < .05) overall muscle strength and muscle power with RT, with no differences between groups. From baseline to POST, the BEEF group had increased concentrations of high-density lipoprotein cholesterol ( P = .025; HDL-C), low-density lipoprotein cholesterol ( P = .027; LDL-C), and total cholesterol ( P = .015: CHOL), with no changes ( P > .05) in triacylglycerol (TG), the CHOL/HDL-C ratio, or the TG/HDL-C ratio. The VEG group did not experience within-group changes ( P > .05) in any lipoprotein-lipid parameter. At POST, the concentrations of HDL-C, LDL-C, and CHOL were greater in the BEEF group compared with the VEG group. There were significant interaction effects for HDL-C ( P = .004) and the TG/HDL-C ratio ( P = .022). Multiple regression analysis determined that, regardless of intervention, change in the saturated fat/fiber ratio (SF/fiber) predicted CHOL (adjusted R 2 = 0.34); the SF/fiber ratio predicted LDL-C (adjusted R 2 = 0.36); the cholesterol/fiber intake ratio predicted HDL-C (adjusted R 2 = 0.26), and the change in carbohydrate intake predicted the CHOL/HDL-C ratio (adjusted R 2 = 0.37) and TG (adjusted R 2 = 0.44).

CONCLUSIONS

These results suggest that the lipoprotein-lipid profile in these older men was differentially affected by supplementation with beef versus soy-based foods during RT. Regardless of group, the lipoprotein-lipid changes were predicted by differences in the SF/fiber ratio and cholesterol/fiber ratio and increases in carbohydrate intake over time.

Megestrol acetate-induced weight gain does not negatively affect blood lipids in elderly men: effects of resistance training and testosterone replacement

BACKGROUND

Megestrol acetate (MA) has been used to stimulate weight gain in elderly populations, with the majority of the weight gain being adipose tissue. Because of the increased energy intake and adipose tissue accrual with MA, it may have a negative effect on circulating lipids. Thus, in this study we examined the effects of MA--alone and in combination with resistance training and/or testosterone replacement--on blood lipids.

METHODS

All subjects (n = 28) received MA and were randomly assigned to one of four groups: 1) placebo (P) injections, 2) resistance training and P (RT+P), 3) weekly injections of testosterone (T; 100 mg/week), or 4) RT and T (RT+T).

RESULTS

A significant time effect was observed for total cholesterol (p = 0.0006) and high density lipoprotein (HDL) cholesterol (p = .0003) with the mid and post time points being significantly lower than the pre time points for both variables. For the total cholesterol to HDL ratio, no significant differences between groups or over time (time effect: ) were observed. For triglycerides, there tended to be a time effect (p = .061), with the mid and post time points being lower than the pre time point; however, this effect was not statistically significant.

CONCLUSIONS

Because it appears from our data that MA does not cause adverse blood lipid changes, the decision to use it should be based on other factors.

Battling insulin resistance in elderly obese people with type 2 diabetes: bring on the heavy weights

Exercise improves insulin resistance and has beneficial effects in preventing and treating type 2 diabetes. However, aerobic exercise is hindered in many type 2 diabetic patients because of advancing age, obesity, and other comorbid conditions. Weight lifting or progressive resistance training (PRT) offers a safe and effective exercise alternative for these people. PRT promotes favorable energy balance and reduced visceral fat deposition through enhanced basal metabolism and activity levels while counteracting age- and disease-related muscle wasting. PRT improves insulin sensitivity and glycemic control; increases muscle mass, strength, and endurance; and has positive effects on bone density, osteoarthritic symptoms, mobility impairment, self-efficacy, hypertension, and lipid profiles. PRT also alleviates symptoms of anxiety, depression, and insomnia in individuals with clinical depression and improves exercise tolerance in individuals with cardiac ischemic disease and congestive heart failure; all of these aspects are relevant to the care of diabetic elders. Moreover, PRT is safe and well accepted in many complex patient populations, including very frail elderly individuals and those with cardiovascular disease. The greater feasibility of using PRT over aerobic exercise in elderly obese type 2 diabetic individuals because of concomitant cardiovascular, arthritic, and other disease provides a solid rationale for investigating the global benefits of PRT in the management of diabetes.

Performance and physiologic adaptations to resistance training

Weight lifting, or resistance training, is a potent stimulus to the neuromuscular system. Depending on the specific program design, resistance training can enhance strength, power, or local muscular endurance. These improvements in performance are directly related to the physiologic adaptations elicited through prolonged resistance training. Optimal resistance training programs are individualized to meet specific training goals. When trained properly (i.e., similar intensity and volume), these functional and physiologic adaptations are similarly impressive among women and the aged as they are among young men. Yet, in contrast to relative measurements, sex and age differences exist in the absolute magnitude of adaptation. Of equal importance, perhaps most notably among the elderly, are the important health benefits that may also be derived from resistance training. For example, bone density, insulin sensitivity, and co-morbidities associated with obesity can be effectively managed with resistance exercise when it is conducted on a regular basis. The extent of the functional and health benefits to be accrued from resistance training depend on factors such as initial performance and health status, along with the specification of program design variables such as frequency, duration, intensity, volume, and rest intervals.

Dietary protein adequacy and lower body versus whole body resistive training in older humans

This study assessed the effects of long-term consumption of the United States Recommended Dietary Allowance (RDA) for protein by older people who were sedentary or performed resistive training (RT) on body composition, skeletal muscle size and protein metabolism, and if the number of muscle groups trained influenced the muscle hypertrophy response to RT. Twelve men and 17 women (age range 54-78 years) completed this 14 week controlled diet and exercise study. Throughout the study, each subject completely consumed daily euenergetic menus that provided the RDA of 0.8 g protein kg(-1) day(-1). From study weeks 3-14 (weeks RT1-RT12), 10 subjects (four men, six women) performed whole body RT (WBRT), nine subjects (four men, five women) performed lower body RT (LBRT) and 10 subjects (four men, six women) remained sedentary (SED). Both the LBRT and WBRT groups performed knee extension and flexion exercises, and the WBRT group also performed chest press and arm pull exercises (three sets per exercise at 80 % of one repetition maximum, 3 days per week for 12 weeks). From week 2 (baseline) to week RT12, muscle strength increased in muscle groups trained in the LBRT and WBRT groups, and was not changed in the SED group. From baseline to week RT12, whole body muscle mass and protein-mineral mass were not changed, fat-free mass (P = 0.004) and total body water (P = 0.013) were decreased, and percentage body fat was increased (P = 0.011) in these weight-stable older people, independent of group assignment. The RT-induced increases in mid-thigh muscle area (from computed tomography scans) were comparable in the LBRT and WBRT groups (2.13 +/- 1.26 cm(2) and 2.17 +/- 1.24 cm(2), respectively), and were different from those in the SED group, which lost muscle area (-1.74 +/- 0.57 cm(2); group-by-time P < 0.05). From baseline to week RT12, 24 h urinary total nitrogen excretion decreased (P < 0.001), nitrogen balance shifted from near equilibrium to positive, whole body leucine oxidation (from the infusion of L-[(13)C]leucine) decreased (P < 0.05) and net (postabsorptive vs. postprandial) leucine balance (P < 0.05) increased from near equilibrium to positive, with no differences in responses over time among the three groups. In conclusion, the number of muscle groups trained did not influence whole body protein metabolism or RT-induced muscle hypertrophy in older people. Most of these data are consistent with a successful adaptation to the RDA for protein. However, research should continue to question whether the decreases in fat-free mass and total body water observed in all subjects, and the decrease in mid-thigh muscle area in the SED group, are physiological accommodations, and whether the RDA for protein might be marginally inadequate for older people to maintain skeletal muscle.

Response of Blood Lipids to Physical Exercise in Elderly Subjects

Regular physical activity plays an important role in nonpharmacologic management of hyperlipidemia, in both the primary and secondary prevention of coronary heart disease. Training intensity and duration, health status (especially the presence of cardiovascular disease), and concomitant changes in body mass and dietary habits are the most important factors that can modify the physical activity-blood lipid profile relationship in the elderly. The benefit of regular exercise goes beyond direct influence on blood lipids; it aids in reducing weight, decreasing fat mass, increasing lean body mass, reducing elevated blood pressure, and increasing insulin sensitivity. Regular physical activity has become widely recommended as an important element of healthy and successful aging and should be encouraged in individuals without contraindications. (c)2001 CHF, Inc.

Effects of endurance training and resistance training on plasma lipoprotein profiles in elderly women

It has been shown that high levels of high-density lipoprotein (HDL) cholesterol and low levels of low-density lipoprotein (LDL) cholesterol are associated with health maintenance in older women, but the few studies that have examined the relationship between exercise and plasma lipoprotein levels in this elderly population have been equivocal. In addition, there are no studies that examine the plasma lipoprotein response of two different types of exercise in a group of active but nonexercising women. Thus, the effects of exercise training on plasma lipoprotein levels in elderly women remain unclear. The purpose of this research was to examine the effects of endurance and resistance exercise on plasma lipoprotein levels in elderly women who were active but nonexercising prior to the study. A total of 45 healthy, active women, aged 70-87 years, were randomly assigned to either an aerobic training (AT, 76 +/- 5 years, n = 15), resistance training (RT, 73 +/- 3 years, n = 15), or control (C, 74 +/- 5 years, n = 15) group. The AT group walked 3 days a week at 70% heart rate reserve. The duration on day 1 was 20 minutes, and it was increased by 5 minutes each day until subjects were walking for 50 minutes (week 3). The exercise training session for the RT group consisted of one to three sets of eight repetitions of eight different exercises at an eight repetition maximum; the C group maintained normal activity. Weight and diet were unchanged across groups. The exercise interventions lasted 10 weeks. Blood samples were obtained from all subjects at week 0 and week 11. Training resulted in a significant decrease in 1-mile walk times and heart rate at completion of the walk for the AT group and a significant increase in eight repetition maximum of all RT exercises. Both AT and RT groups experienced increased HDL cholesterol and decreased triglycerides at week 11 compared with week 0. There were no positive changes in control lipoproteins. Both triglycerides and the total cholesterol to HDL ratio increased significantly while total cholesterol, HDL cholesterol, and LDL cholesterol remained unchanged. The RT group also had significantly lower LDL cholesterol and total cholesterol compared with controls at week 11. Both RT and endurance training resulted in favorable changes to plasma lipoprotein levels for elderly women in only 10 weeks. The fact that this occurred without concurrent changes in weight or diet is an indication that high-intensity exercise alone can be used to modify lipoproteins in populations of healthy elderly women.

Muscle size responses to strength training in young and older men and women

OBJECTIVES

To examine the possible influences of age and gender on muscle volume responses to strength training (ST).

DESIGN

Prospective intervention study.

SETTING

University of Maryland Exercise Science and Wellness Research Laboratories.

PARTICIPANTS

Eight young men (age 20-30 years), six young women (age 20-30 years), nine older men (age 65-75 years), and ten older women (age 65-75 years).

INTERVENTION

A 6-month whole-body ST program that exercised all major muscle groups of the upper and lower body 3 days/week.

MEASUREMENTS

Thigh and quadriceps muscle volumes and mid-thigh muscle cross-sectional area (CSA) were assessed by magnetic resonance imaging before and after the ST program.

RESULTS

Thigh and quadriceps muscle volume increased significantly in all age and gender groups as a result of ST (P < .001), with no significant differences between the groups. Modest correlations were observed between both the change in quadriceps versus the change in total thigh muscle volume (r = 0.65; P < .001) and the change in thigh muscle volume versus the change in mid-thigh CSA (r = 0.76, P < .001).

CONCLUSIONS

The results indicate that neither age nor gender affects muscle volume response to whole-body ST. Muscle volume, rather than muscle CSA, is recommended for studying muscle mass responses to ST.

Dose-response: variation with age, sex, and health status

PURPOSE

The purpose of this study was to summarize the literature on the influence of age, sex, and health status on the changes in systolic (SBP) and diastolic blood pressure (DBP), triglycerides (TG), and high-density lipoprotein cholesterol (HDL-C) consequent to exercise training.

METHODS

A MEDLINE search was performed from January 1966 through August 2000 to identify studies that have investigated the effects of age, sex, and health status on the changes in the outcome variables with exercise training. References from these studies and from review and meta-analysis studies were also reviewed.

RESULTS AND CONCLUSIONS

The results indicate that age has little or no influence on the changes in SBP, DBP, TG, and HDL-C in response to exercise training. When looking at sex, females appear to have an attenuated response to exercise training compared with males with respect to SBP, DBP, and HDL-C, but the data for TG are equivocal. Finally, there appears to be more favorable changes in resting SBP and DBP, TG, and HDL-C in unhealthy subjects (hypertensive and post-MI patients) when compared with healthy subjects.

Resistance exercise training reduces hypertriglyceridemia in HIV-infected men treated with antiviral therapy

Hypertriglyceridemia, peripheral insulin resistance, and trunk adiposity are metabolic complications recently recognized in people infected with human immunodeficiency virus (HIV) and treated with highly active antiretroviral therapy (HAART). These complications may respond favorably to exercise training. Using a paired design, we determined whether 16 wk of weight-lifting exercise increased muscle mass and strength and decreased fasting serum triglycerides and adipose tissue mass in 18 HIV-infected men. The resistance exercise regimen consisted of three upper and four lower body exercises done for 1-1.5 h/day, 4 days/wk for 64 sessions. Dual-energy X-ray absorptiometry indicated that exercise training increased whole body lean mass 1.4 kg (P = 0.005) but did not reduce adipose tissue mass (P = NS). Axial proton-magnetic resonance imaging indicated that thigh muscle cross-sectional area increased 5-7 cm(2) (P < 0.005). Muscle strength increased 23-38% (P < 0.0001) on all exercises. Fasting serum triglycerides were decreased at the end of training (281-204 mg/dl; P = 0.02). These findings imply that resistance exercise training-induced muscle hypertrophy may promote triglyceride clearance from the circulation of hypertriglyceridemic HIV-infected men treated with antiviral therapy.

Exercise training and blood lipids in hyperlipidemic and normolipidemic adults: a meta-analysis of randomized, controlled trials

OBJECTIVE

To determine the effectiveness of exercise training (aerobic and resistance) in modifying blood lipids, and to determine the most effective training programme with regard to duration, intensity and frequency for optimizing the blood lipid profile.

DESIGN

Trials were identified by a systematic search of Medline, Embase, Science Citation Index (SCI), published reviews and the references of relevant trials. The inclusion criteria were limited to randomized, controlled trials of aerobic and resistance exercise training which were conducted over a minimum of four weeks and involved measurement of one or more of the following: total cholesterol (TC), high density lipoprotein (HIDL-C), low density lipoprotein (LDL-C) and triglycerides (TG).

SUBJECTS

A total of 31 trials ( 1833 hyperlipidemic and normolipidemic participants) were included.

RESULTS

Aerobic exercise training resulted in small but statistically significant decreases of 0.10 mmol/L (95% CI: 0.02, 0.18). 0.10 (95% CI: 0.02, 0.19), 0.08 mmol/L (95% CI: 0.02, 0.14), for TC, LDL-C, and TG, respectively, with an increase in HDL-C of 0.05 mmol/L (95% CI: 0.02, 0.08). Comparisons between the intensities of the aerobic exercise programmes produced inconsistent results; but more frequent exercise did not appear to result in greater improvements to the lipid profile than exercise three times per week. The evidence for the effect of resistance exercise training was inconclusive.

CONCLUSIONS

Caution is required when drawing firm conclusions from this study given the significant heterogeneity with comparisons. However, the results appear to indicate that aerobic exercise training produced small but favourable modifications to blood lipids in previously sedentary adults.