Resistance training enhances delayed memory in healthy middle-aged and older adults: A randomised controlled trial

Effects of resistance exercise and whey protein supplementation on cognitive function in older men: secondary analysis of a randomised, double-blind, placebo-controlled trial

PURPOSE

Ageing is associated with cognitive decline. This study investigated the individual and combined effects of resistance exercise (RE) and whey protein supplementation (PRO) on cognitive function in older men.

METHODS

In a pooled-groups analysis, 36 older men (age: 67 ± 4 years) were randomised to either RE (2 x/week; n = 18) or no exercise (NE; n = 18), and either PRO (2 × 25 g/d whey protein isolate; n = 18) or control (CON, 2 × 23.75 g maltodextrin/d; n = 18). A sub-analysis was also conducted between RE + CON (n = 9) and RE + PRO (n = 9). At baseline and 12 weeks, participants completed a battery of neuropsychological tests (CANTAB; Cambridge Cognition, UK) and neurobiological, inflammatory, salivary cortisol and insulin sensitivity biomarkers were quantified.

RESULTS

PRO improved executive function z-score (+0.31 ± 0.08) greater than CON (+0.06 ± 0.08, P = 0.03) and there was a trend towards improved global cognitive function (P = 0.053). RE and RE + PRO did not improve any cognitive function domains (p ≥ 0.07). RE decreased tumor necrosis factor-alpha (P = 0.02) and interleukin-6 (P = 0.048) concentrations compared to NE, but changes in biomarkers did not correlate with changes in cognitive domains. Muscle strength (r = 0.34, P = 0.045) and physical function (ρ = 0.35-0.51, P < 0.05) outcomes positively correlated with cognitive function domains at baseline, but only Δskeletal muscle index correlated with Δepisodic memory (r = 0.34, P = 0.046) following the intervention.

CONCLUSION

In older men, PRO improved cognitive function, most notably executive functioning. RE did not improve any cognitive function domains but did decrease biomarkers of systemic inflammation. No synergistic effects were observed.

The Combined Effect of Tribulus terrestris Hydroalcoholic Extract and Swimming Exercise on Memory and Oxidative Stress in Old Male Rats

BACKGROUND AND OBJECTIVE

This study aims to assess the effect of swim exercise along with consumption of bindii hydroalcoholic extract on memory and the oxidative stress markers in old male rats.

MATERIALS AND METHODS

This study was conducted on 32 old (400-500 g) and eight young male Wistar rats. The groups included young, old, old bindii (200 mg/kg), old exercise, and old bindii exercise (concurrent swimming training). All interventions were performed within 14 days. The animals' spatial memory was evaluated by the Y maze, radial maze, and shuttle box, Oxidative stress factors were also measured.

RESULTS

Compared to the old control group, the bindii extract along with swimming exercise significantly increased the periodic behavior percentage in the Y maze and the delay time in entry into the dark chamber in the shuttle box but no significant difference was seen in the reference memory error in the radial maze. Also, a significant increase in the amount of catalase (CAT) and antioxidant capacity (TAC) and a significant decrease in the amount of malondialdehyde (MDA) were observed in all treatment groups.

CONCLUSION

These results show that exercise, along with the bindii extract consumption, can improve spatial and avoidance memory in old rats probably through the reduction of oxidative stress effects.

Cognitive Performance following Single- or Multi-Session Exercise Intervention in Middle Age: A Systematic Review

BACKGROUND

Research in modifiable behaviors, like exercise, on risk for dementia is increasing. Although many studies focus on older adults, brain pathology for Alzheimer's Disease can begin in middle age, suggesting an ideal target for intervention.

METHODS

We conducted a systematic review from exercise intervention studies on cognitive function among healthy, middle-aged participants (45-65). We searched multiple databases (PubMed, PsycINFO, MEDLINE, Cochrane Central Register of Controlled Trials, Google Scholar) for studies using standard, validated, neuropsychological measures following either single- or multi-session interventions in cognitively-unimpaired, middle-aged adults.

RESULTS

We identified 13 eligible studies. There was notable heterogeneity across studies, with varying design, measures, interventions, and results. Results from single-session studies showed improvement in response inhibition, while results for cognitive flexibility were mixed. No significant changes were found on measures of attention, working memory, or processing speed. Results from multi-session studies were more varied. Verbal memory was found to improve while performance on tests of attention and working memory, processing speed, and executive function were mixed.

CONCLUSION

Importantly, for both single-session and multi-session studies, there was no standard set of neuropsychological tests administered, making it more difficult to synthesize the findings into a single narrative. We end with a discussion on future directions and implementation.

Factors for optimizing intervention programs for cognition in older adults: the value of exergames

This review presents factors that could optimize the effectiveness of an intervention program on cognitive health in older adults. Combined, multi-dimensional and interactive programs appear to be relevant. On one hand, for the characteristics to be implemented in the physical dimension of a program, multimodal interventions stimulating the aerobic pathway and muscle strengthening during the solicitation of gross motor activities, seem to be interesting. On the other hand, regarding the cognitive dimension of a program, complex and variable cognitive stimuli appear to hold the greatest promise for generating cognitive benefits and the broadest transfers to untrained tasks. The field of video games also brings interesting enrichment through the gamification of situations and the feeling of immersion. However, some gray areas remain to be clarified, notably the ideal response dose, the balance between physical and cognitive solicitation and the programs’ customization.

Randomised controlled trials for the prevention of cognitive decline or dementia: A systematic review

Dementia prevention research has progressed rapidly in recent years, with publication of several large lifestyle intervention trials, and renewed interest in pharmacological interventions, notably for individuals with Alzheimer's disease biomarkers, warranting an updated review of results and methodology. We identified 112 completed trials testing the efficacy of single-domain pharmacological (n = 33, 29%), nutritional (n = 27, 24%), physical activity (n = 18, 16%) and cognitive stimulation (n = 13, 12%), or multidomain (n = 22, 20%) interventions on incident dementia, or a relevant intermediate marker (e.g. cognitive function, biomarkers or dementia risk scores) in people without dementia. The earliest trials tested pharmacological interventions or nutritional supplements, but lifestyle interventions predominated in the last decade. In total, 21 (19%) trials demonstrated a clear beneficial effect on the pre-specified primary outcome (or all co-primary outcomes), but only two (10%) were large-scale (testing blood pressure lowering (Syst-Eur) or multidomain (FINGER) interventions on incident dementia and cognitive change in cognitive function, respectively). Of the 116 ongoing trials, 40% (n = 46) are testing multidomain interventions. Recent methodological shifts concern target populations, primary outcome measures, and intervention design, but study design remains constant (parallel group randomised controlled trial). Future trials may consider using adaptive trials or interventions, and more targeted approaches, since certain interventions may be more effective in certain subgroups of the population, and at specific times in the life-course. Efforts should also be made to increase the representativeness and diversity of prevention trial populations.

The Effect of Resistance Training in Healthy Adults on Body Fat Percentage, Fat Mass and Visceral Fat: A Systematic Review and Meta-Analysis

BACKGROUND

Resistance training is the gold standard exercise mode for accrual of lean muscle mass, but the isolated effect of resistance training on body fat is unknown.

OBJECTIVES

This systematic review and meta-analysis evaluated resistance training for body composition outcomes in healthy adults. Our primary outcome was body fat percentage; secondary outcomes were body fat mass and visceral fat.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

We searched five electronic databases up to January 2021.

ELIGIBILITY CRITERIA

We included randomised trials that compared full-body resistance training for at least 4 weeks to no-exercise control in healthy adults.

ANALYSIS

We assessed study quality with the TESTEX tool and conducted a random-effects meta-analysis, with a subgroup analysis based on measurement type (scan or non-scan) and sex (male or female), and a meta-regression for volume of resistance training and training components.

RESULTS

From 11,981 records, we included 58 studies in the review, with 54 providing data for a meta-analysis. Mean study quality was 9/15 (range 6-15). Compared to the control, resistance training reduced body fat percentage by - 1.46% (95% confidence interval - 1.78 to - 1.14, p < 0.0001), body fat mass by - 0.55 kg (95% confidence interval - 0.75 to - 0.34, p < 0.0001) and visceral fat by a standardised mean difference of - 0.49 (95% confidence interval - 0.87 to - 0.11, p = 0.0114). Measurement type was a significant moderator in body fat percentage and body fat mass, but sex was not. Training volume and training components were not associated with effect size. Resistance training reduces body fat percentage, body fat mass and visceral fat in healthy adults.

STUDY REGISTRATION

osf.io/hsk32.

Swimming exercise improves short- and long-term memories: Time-course changes

The beneficial effects of exercise training on memory formation are well documented. However, the memory enhancement profile following the time-course of exercise training remains unknown. In this investigation, changes in the spatial hippocampal memory following a time-course of swimming exercise training were examined. Young adult Wistar rats were tested for both short-term and long-term memories using the radial arm water maize (RAWM) paradigm following 0, 1, 7, 14, and 28 days of swimming exercise training (60 min per day, 5 days/week)s. The mean total errors on RAWM during the learning phase and memory testing remained the same (p > 0.5) after 1 day of swimming exercise. On the other hand, swimming exercise-induced significant enhancement to the learning phase and memory formation after 7 days of training (p < 0.01). Errors decreased (p < 0.0001) after 7 days of training and remained lower (p < 0.0001) than baseline without differences between 7, 14, and 28 days (p > 0.5). Similarly, short- and long-term memories improved after 7 days (p < 0.05) of training as compared to the baseline without differences between 7, 14, and 28 days (p > 0.05). The time course of improvement of learning and both short- and long-term memories after swimming exercise were evident after 7 days and plateaued thereafter. Results of the current study could form the base for future utilization of exercises to enhance cognitive function in healthy individuals.

Effect of regular resistance training on memory in older adults: A systematic review

The purpose of this study was to evaluate the effect of regular resistance training on memory in older adults.

METHODS

Eight databases (PubMed, Cochrane Library, EMBASE, Web of Science, SinoMed, China National Knowledge Infrastructure (CNKI), China Science and Technology Periodical Database (VIP) and Wanfang) were searched from their inception to March 24, 2021. The data included in the study were analysed according to the Cochrane handbook using Review Manager 5.3 software.

RESULTS

Eighteen eligible randomized controlled trials (RCTs) with a total of 1365 older adults were identified that met the inclusion criteria for the systematic review. Compared with no specific exercise or a low intensity exercise control, regular resistance training significantly improved working memory (standardized mean difference (SMD): 0.27, 95% confidence interval (CI): 0.11, 0.42, P < 0.001), immediate memory (SMD: 0.27, 95% CI: 0.01, 0.54, P = 0.04), and short-term memory (SMD: 0.68, 95% CI: 0.23,1.14, P = 0.003) but had no significant impact on verbal memory (SMD: 0.15, 95% CI: -0.40, 0.71, P = 0.59) or delayed memory (SMD: 0.01, 95% CI: -0.39, 0.42, P = 0.18).

CONCLUSIONS

Regular resistance training has a positive beneficial effect on working memory, immediate memory and short-term memory in older adults. However, due to the limitations of the included studies, these findings should be interpreted cautiously.

Effects of Progressive Resistance Training on Cognition and IGF-1 Levels in Elder Women Who Live in Areas with High Air Pollution

The aim of this study was to determine the effects of a muscular strength programme on the levels of insulin-like growth factor-1 (IGF-1) and cognitive status in elder women with mild cognitive impairment who lived in areas of high air pollution. A total of 157 women participated in the study, distributed in four groups: Active/Clean (AC n = 38) and Active/Pollution (AP n = 37), who carried out a progressive resistance training programme for 24 months, and Sedentary/Clean (SC n = 40) and Sedentary/Pollution (SP n = 42). Maximum strength in the upper and lower limbs (1RM), cognition (Mini-Mental Scale Examination (MMSE)) and blood IGF-1 were evaluated. At the beginning of the intervention, there were no differences between the groups in the assessed variables. The active groups which carried out the resistance training programme (AC and AP), registered better results in IGF-1 than the sedentary groups. These differences were statistically significant in AC vs. SC (p < 0.01) and AP vs. SC (p < 0.05). Regarding MMSE, group AC registered the highest score increases (+8.2%) (significantly better than the other groups), while group SP worsened (−7%) significantly compared to the other three groups. In conclusion, resistance training had a positive effect on IGF-1, while sedentary behaviour and air pollution had a negative effect on cognitive status.

An Intense, But Ecologically Valid, Resistance Exercise Session Does Not Alter Growth Factors Associated With Cognitive Health

The purpose of this investigation was to assess the acute changes in growth factors associated with cognitive health following two ecologically valid, intense resistance exercise sessions. Twenty-nine late-middle-aged adults performed one session of either (a) moderate-load resistance exercise or (b) high-load resistance exercise. Venous blood was collected prior to warm-up, immediately following exercise and 30 min following exercise. Serum was analyzed for brain-derived neurotrophic factor, insulin-like growth factor 1, and vascular endothelial growth factor. Session intensity was determined by blood lactate concentration and session rating of perceived exertion. Postexercise blood lactate was greater following moderate-load when compared with high-load resistance exercise. Subjective session intensity was rated higher by the session rating of perceived exertion following moderate-load when compared with high-load resistance exercise. No differences were observed in serum growth factor levels between groups. Ecologically valid and intense moderate-load or high-load exercise methods do not alter serum growth factor levels in late-middle-aged adults.

Twelve weeks of resistance training does not influence peripheral levels of neurotrophic growth factors or homocysteine in healthy adults: a randomized-controlled trial

INTRODUCTION

There is growing evidence for a preventative effect of resistance training on cognitive decline through physiological mechanisms; yet, the effect of resistance training on resting growth factors and homocysteine levels is incompletely understood. This study aimed to investigate the effect of intense resistance training, for 12 weeks, on changes in peripheral growth factors and homocysteine in late middle-aged adults.

METHODS

45 healthy adults were enrolled into the single-site parallel groups' randomized-controlled trial conducted at the Department of Exercise Science, Strength and Conditioning Laboratory, Murdoch University. Participants were allocated to the following conditions: (1) high-load resistance training (n = 14), or (2) moderate-load resistance training (n = 15) twice per week for 12 weeks; or (3) non-exercising control group (n = 16). Data were collected from September 2016 to December 2017. Fasted blood samples were collected at baseline and within 7 days of trial completion for the analysis of resting serum brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1, vascular endothelial growth factor, and plasma homocysteine levels.

RESULTS

No differences in baseline to post-intervention change in serum growth factors or plasma homocysteine levels were observed between groups. A medium effect was calculated for BDNF change within the high-load condition alone (+ 12.9%, g = 0.54).

CONCLUSIONS

High-load or moderate-load resistance training twice per week for 12 weeks has no effect on peripheral growth factors or homocysteine in healthy late middle-aged adults.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12616000690459.