The epidemiology of muscle-strengthening exercise in Europe: A 28-country comparison including 280,605 adults

Resistance Exercise Participation in Community-Dwelling Older Adults in Korea: Associated Factors and Sex Differences

Background/Objectives: Despite the importance of resistance exercise in older adults, factors associated with participation remain unclear, especially regarding sex differences. This study investigated sociodemographic, behavioral, and comorbidity factors associated with insufficient resistance exercise participation among community-dwelling older adults in Korea, with analyses stratified by sex. Methods: Nationally representative cross-sectional data from 8671 participants aged ≥65 years (3758 men and 4913 women; mean age 72.8) were analyzed using the 6th-8th Korea National Health and Nutrition Examination Surveys (2014-2019). Complex-sample multivariable logistic regression identified factors associated with insufficient resistance exercise overall and by sex. Results: Women had a higher prevalence of insufficient resistance exercise than men (91.27% vs. 71.04%, p < 0.001). Older age groups, particularly those aged ≥80 years (OR: 2.39; 95% CI: 1.86-3.07), and those with lower education (OR: 1.56; 95% CI: 1.33-1.82), rural residence (OR: 1.89; 95% CI: 1.49-2.38), low household income, (OR: 1.45; 95% CI: 1.13-1.88), insufficient aerobic exercise (OR: 1.68; 95% CI: 1.46-1.94), current smoking (OR: 1.70; 95% CI: 1.26-2.29), and diabetes (OR: 1.28; 95% CI: 1.09-1.51) were independently associated with a higher likelihood of insufficient resistance exercise. The association of household income, current smoking, hypertension, and diabetes with resistance exercise adherence showed differences in sex-stratified analyses. Conclusions: Multiple sociodemographic, behavioral, and comorbid factors are linked to resistance exercise adherence among older Koreans. Tailored, sex-specific interventions are needed to promote resistance exercise in this population, informing public health strategies and further research on effective approaches for diverse older adults.

How many adults have sufficient muscle-strengthening exercise and the associated factors: A systematic review consisting of 2,629,508 participants

Purpose

The aim of this systematic review was to (1) estimate the prevalence of adhering to the MSE guidelines (at least 2 times/days a week) among adults; and (2) synthesize evidence on the correlates of adhering to the MSE guidelines.

Methods

Five electronic databases were searched (March 2022), with a total of 30 observational studies consisting of 2,629,508 participants meeting the eligibility criteria. A meta-analysis was conducted to pool the prevalence of adhering to the MSE guidelines using the results of 21 eligible studies (study aim 1); and data reporting correlates of adhering to the MSE guidelines using 12 eligible studies were synthesized and categorized based on the Socioecological Model Framework (study aim 2).

Results

Overall, 22.8 % (95%CI: 18.18 % ─ 27.77 %) of adults adhered to the MSE guidelines, and 23 potential correlates at five levels were examined. Five variables (i.e., sex, age, education level, socioeconomic status) at the sociodemographic level and two variables (i.e., body mass index, self-rated health) at the physical related level were identified as consistent correlates, but displaying weak to moderate association strengths.

Conclusions

Less than a quarter of adults meet the MSE guidelines and multidimensional correlates are associated with the adherence to the guidelines, particularly sociodemographic correlates (e.g., sex, age, and educational level). Findings highlight the need to further promote the importance of engaging in MSE among adults and investing effective interventions that not only provide opportunities for MSE for adults, but also facilitate the development of skills and confidence to engage in MSE.

Weight training and risk of all-cause, cardiovascular disease and cancer mortality among older adults

BACKGROUND

While previous studies indicate muscle-strengthening exercises may reduce mortality risk, further research is needed to increase certainty of the evidence. We investigated overall and dose-response associations between weight training and the risks of all-cause, cardiovascular disease (CVD) and cancer mortality in a large cohort of older adults with long follow-up time and a large number of deaths. We also investigated the joint associations of weight training and aerobic exercise with mortality risk.

METHODS

Weight training was assessed via self-report in 2004-05 in the National Institutes of Health-American Association of Retired Persons (NIH-AARP) Diet and Health Study (USA; n = 216 339), with follow-up to 2019. Cox regression estimated the hazard ratios (HR) and 95% confidence intervals (CI) for the associations between weight training and mortality, after adjusting for confounders including aerobic exercise.

RESULTS

Around 25% of participants [mean age = 69.9 years (standard deviation = 5.4), 58% men] reported engaging in weight training over the past year, and there were 79 107 (37%) deaths. Engaging in any weight training (vs none) was associated with lower risks of all-cause (HR = 0.94; 95% CI = 0.93-0.96), CVD (HR = 0.92; 95% CI = 0.90-0.95) and cancer mortality (HR = 0.95; 95% CI = 0.92-0.98). More time spent in weight training was associated with only marginally greater risk reductions. Larger risk reductions were observed among women than men. Performing both aerobic exercise and weight training conferred the greatest mortality risk reduction; weight training was not associated with mortality risk among participants who did no aerobic exercise.

CONCLUSION

Performing any amount of weight training lowered mortality risk.

Impact of a 16-week strength training program on physical performance, body composition and cardiac remodeling in previously untrained women and men

Even if more and more women are involved in strength-training (ST) programs in fitness centers, studies on strength gain, body composition, and cardiac remodeling were mainly conducted in men and whether they are similar in women remains to be explored. In this context, the aim of our study was to assess the effect of a supervised ST program on strength gains, body composition, and cardiac remodeling in previously untrained women and men. 17 healthy and previously untrained young women and 17 young men participated in a supervised 16-week ST program built according to the recommendation of the American College of Sports Medicine in terms of intensity, and strictly using similar volume and intensity in both groups. Strength performance, body composition, and cardiac remodeling were evaluated every 4 weeks. Cardiac adaptations were assessed using resting echocardiography, including regional 2D-Strain analysis of the left atrium and ventricle (LA and LV, respectively). Despite lower values at baseline, women exhibited similar or even higher strength gains compared to men. ST induced a decrease of body and abdominal fat mass and an increase of lean body mass in both groups. Similar cardiac remodeling was observed in women, and women, including an early and progressive LV and LA enlargement throughout the ST program, without any alteration of LV diastolic and systolic functions. These findings underlie that ST programs are highly suitable for women to enhance their strength performance and their cardiovascular health.

Sedentary time at school and work in Canada

OBJECTIVES

High levels of sedentary time (ST) are associated with poor physical and mental health. Given that Canadians spend a large portion of their days at school and work, they may be important targets for reducing ST. Our objectives are to estimate the daily amount of school and work ST among Canadians, examine differences by subgroups, and determine associations with health.

METHODS

Using the 2020 Canadian Community Health Survey Healthy Living Rapid Response module (N = 5242), the amount of time spent sitting while at school and work was estimated among youth (12-17 years) and adults (18-34 and 35-64 years). Differences by sociodemographics and 24-Hour Movement Guideline adherence were assessed with independent t-tests. Associations between school and work ST and health indicators were assessed using adjusted logistic regression.

RESULTS

Canadian youth aged 12-17 years and adults aged 18-34 years reported an average of 4.5 and 5.2 h/day of school ST, respectively. Adults 18-34 years and 35-64 years reported an average of 3.9 and 4.0 h/day of work ST, respectively. School and work ST differed within several subgroups. Among adults 18-34 years, higher school ST was associated with a reduced odds of 'excellent/very good' mental health, whereas higher work ST was associated with a greater likelihood of reporting 'excellent/very good' general health.

CONCLUSION

Canadian youth and working-age adults report an average of 4-5 h/day sedentary at school or work. This is the first study estimating school and work ST in a representative sample of Canadians and will aid in increasing awareness of setting-specific behaviours to better inform targeted interventions including addressing inequalities in ST.

Resistance exercise for anxiety and depression: efficacy and plausible mechanisms

Anxiety and depressive symptoms and disorders are prevalent and poorly treated. The salutary benefits of resistance exercise training (RET), a potential alternative therapy, are well established, but mental health effects are understudied. This forum article summarizes the most rigorous evidence regarding efficacy of resistance exercise and provides a primer for putative psychobiological mechanisms.

Weekly minimum frequency of one maximal eccentric contraction to increase muscle strength of the elbow flexors

PURPOSE

Our previous study showed that one 3-s maximal eccentric contraction a day performed 5 days a week for 4 weeks (5DW) increased maximal voluntary contraction (MVC) strength of the elbow flexors more than 10%. The present study examined whether muscle strength would still increase when the frequency was reduced to 2 days or 3 days per week.

METHODS

Twenty-six healthy young adults were recruited in the present study and placed to two groups (n = 13/group) based on the weekly frequency of the one 3-s maximal eccentric contraction for two (2DW) or three days per week (3DW) for 4 weeks. Changes in MVC-isometric, MVC-concentric, MVC-eccentric torque of the elbow flexors, and muscle thickness of biceps brachii and brachialis (MT) before and after the 4-week training were compared between 2DW and 3DW groups, and also compared to the 5DW group in the previous study.

RESULTS

The 2DW group showed no significant changes in MVC torque. Significant (P < 0.05) increases in MVC-concentric (2.5 ± 10.4%) and MVC-eccentric (3.9 ± 4.9%) torque were observed for the 3DW group, but the magnitude of the increase was smaller (P < 0.05) than that presented by the 5DW group (12.8 ± 9.6%, 12.2 ± 7.8%). No significant changes in MT were evident for any of the groups.

CONCLUSION

These results suggest that at least three days a week are necessary for the one 3-s maximal eccentric contraction to be effective for increasing muscle strength, and more frequent sessions in a week (e.g., 5 days) appear to induce greater increases in muscle strength.

"It Makes You Feel Alive and Younger…but It's Stressful …My Back and Legs Ache": A Focus Group Study Encouraging Resistance Training Around Retirement

Muscle weakness is a key component of age-related conditions such as sarcopenia and frailty. Resistance training is highly effective at preventing and treating muscle weakness; however, few adults meet recommended levels. Retirement may be a key life-stage to promote resistance training. We carried out a virtual focus group study to explore motivators and barriers to resistance training around the time of retirement, with the aim of determining strategies and messages to increase its uptake. The five focus groups (n = 30) were recorded, transcribed and thematically analysed. We found that resistance training was positively viewed when associated with immediate and long-term health and wellbeing benefits and had a social dimension; but there was a lack of understanding as to what constitutes resistance training, the required intensity level for effects; the role of pain; and the consequences of muscle weakness.

Exercise instructors are not consistently implementing the strength component of the UK chief medical officers' physical activity guidelines in their exercise prescription for older adults

Strength training recommendations have been embedded within the UK's Chief Medical Officers' physical activity guidelines since 2011. There is limited evidence that these recommendations are used by exercise instructors in the community to underpin strength training prescription in the older adult population. This study aimed to explore exercise instructors' awareness and utilisation of the guidelines when prescribing strength training to older adults. Fifteen exercise instructors working with older adults in the UK participated in one online interview. A general inductive approach was conducted and thematic analysis allowed for major themes to be identified from the raw data. We found that most exercise instructors (n = 9), but not all (n = 6), were aware of the guidelines. Only one instructor (n = 1) had reportedly implemented the guidelines into their practice; other instructors reported that the guidelines were irrelevant. Instead, each of the instructors had their preferred sources of information that they relied on to underpin their exercise prescription, and each had their own interpretation of 'evidence-based strength training.' This individualised interpretation resulted in exceptionally varied prescription in the community and does not necessarily align with the progressive, evidence-based prescription known to build muscular strength. We suggest that (i) more detail on how to build muscular strength be embedded within the guidelines, (ii) a handbook on how to implement the guidelines be made available, (iii) theoretical and practical teaching materials and courses be updated, and/or (iv) a re-(education) of exercise instructors already in the field may be necessary to bring about a consistent, evidence-based strength prescription necessary for the best possible health and longevity outcomes for our ageing population.

Connective Adaptive Resistance Exercise (CARE) Machines for Accentuated Eccentric and Eccentric-Only Exercise: Introduction to an Emerging Concept

Eccentric resistance exercise emphasizes active muscle lengthening against resistance. In the past 15 years, researchers and practitioners have expressed considerable interest in accentuated eccentric (i.e., eccentric overload) and eccentric-only resistance exercise as strategies for enhancing performance and preventing and rehabilitating injuries. However, delivery of eccentric resistance exercise has been challenging because of equipment limitations. Previously, we briefly introduced the concept of connected adaptive resistance exercise (CARE)-the integration of software and hardware to provide a resistance that adjusts in real time and in response to the individual's volitional force within and between repetitions. The aim of the current paper is to expand this discussion and explain the potential for CARE technology to improve the delivery of eccentric resistance exercise in various settings. First, we overview existing resistance exercise equipment and highlight its limitations for delivering eccentric resistance exercise. Second, we describe CARE and explain how it can accomplish accentuated eccentric and eccentric-only resistance exercise in a new way. We supplement this discussion with preliminary data collected with CARE technology in laboratory and non-laboratory environments. Finally, we discuss the potential for CARE technology to deliver eccentric resistance exercise for various purposes, e.g., research studies, rehabilitation programs, and home-based or telehealth interventions. Overall, CARE technology appears to permit completion of eccentric resistance exercise feasibly in both laboratory and non-laboratory environments and thus has implications for researchers and practitioners in the fields of sports medicine, physiotherapy, exercise physiology, and strength and conditioning. Nevertheless, formal investigations into the impact of CARE technology on participation in eccentric resistance exercise and clinical outcomes are still required.

Narrative Review of Sex Differences in Muscle Strength, Endurance, Activation, Size, Fiber Type, and Strength Training Participation Rates, Preferences, Motivations, Injuries, and Neuromuscular Adaptations

ABSTRACT

Nuzzo, JL. Narrative review of sex differences in muscle strength, endurance, activation, size, fiber type, and strength training participation rates, preferences, motivations, injuries, and neuromuscular adaptations. J Strength Cond Res 37(2): 494-536, 2023-Biological sex and its relation with exercise participation and sports performance continue to be discussed. Here, the purpose was to inform such discussions by summarizing the literature on sex differences in numerous strength training-related variables and outcomes-muscle strength and endurance, muscle mass and size, muscle fiber type, muscle twitch forces, and voluntary activation; strength training participation rates, motivations, preferences, and practices; and injuries and changes in muscle size and strength with strength training. Male subjects become notably stronger than female subjects around age 15 years. In adults, sex differences in strength are more pronounced in upper-body than lower-body muscles and in concentric than eccentric contractions. Greater male than female strength is not because of higher voluntary activation but to greater muscle mass and type II fiber areas. Men participate in strength training more frequently than women. Men are motivated more by challenge, competition, social recognition, and a desire to increase muscle size and strength. Men also have greater preference for competitive, high-intensity, and upper-body exercise. Women are motivated more by improved attractiveness, muscle "toning," and body mass management. Women have greater preference for supervised and lower-body exercise. Intrasexual competition, mate selection, and the drive for muscularity are likely fundamental causes of exercise behaviors in men and women. Men and women increase muscle size and strength after weeks of strength training, but women experience greater relative strength improvements depending on age and muscle group. Men exhibit higher strength training injury rates. No sex difference exists in strength loss and muscle soreness after muscle-damaging exercise.

Correlates of and changes in aerobic physical activity and strength training before and after the onset of COVID-19 pandemic in the UK: findings from the HEBECO study

OBJECTIVES

Understanding changes in moderate to vigorous aerobic physical activity (MVPA) and muscle-strengthening activity (MSA) at the start of the COVID-19 pandemic and their correlates (socio-demographics, health characteristics, living and exercise conditions and pre-pandemic MVPA/MSA) can inform interventions.

DESIGN

A cross-sectional analysis of retrospective and concurrent data on MVPA/MSA.

SETTING

An online survey in the UK.

PARTICIPANTS

2657 adults (weighted n=2442, 53.6% women) participating in the baseline survey (29 April 2020-14 June 2020) of the HEalth BEhaviours during the COVID-19 pandemic (HEBECO) study.

PRIMARY AND SECONDARY OUTCOME MEASURES

Meeting WHO-recommended levels for MVPA/MSA/both (vs meeting neither) during the first lockdown and changes in MVPA/MSA from before to since the COVID-19 pandemic following stratification for pre-pandemic MVPA/MSA.

RESULTS

A third of adults maintained (30.4%), decreased (36.2%) or increased (33.4%) MVPA. For MSA, the percentages were 61.6%, 18.2% and 20.2%, respectively. MVPA increased or decreased by an average of 150 min/week and 219 min/week, respectively, and MSA by 2 days/week. Meeting both MSA+MVPA recommendations since COVID-19 (vs meeting neither) was positively associated with meeting MVPA+MSA before COVID-19 (adjusted OR (aOR)=16.11, 95% CI 11.24 to 23.07) and education: post-16 years of age (aOR=1.57, 95% CI 1.14 to 2.17), and negatively associated with having obesity (aOR=0.49, 95% CI 0.33 to 0.73), older age (65+ years vs ≤34 years; aOR=0.53, 95% CI 0.32 to 0.87) and annual household income of <50 000 GBP (aOR=0.65, 95% CI 0.46 to 0.91). The odds for decreasing MVPA were lower for white ethnicity (aOR=0.62, 95% CI 0.44 to 0.86), education: post-16 years of age (aOR=0.73, 95% CI 0.58 to 0.91) and access to garden/balcony (aOR=0.75, 95% CI 0.60 to 0.94), and were higher for those living in total isolation (aOR=3.81, 95% CI 2.33 to 6.23), with deteriorated psychological well-being (aOR=1.40, 95% CI 1.15 to 1.71) and conditions limiting physical activity (aOR=1.74, 95% CI 1.27 to 2.39). The odds for decreasing MSA were higher for having overweight (aOR=1.88, 95% CI 1.39 to 2.55), obesity (aOR=23.38, 95% CI 2.23 to 5.14) and being employed (aOR=1.81, 95% CI 1.34 to 2.46).

CONCLUSION

Aerobic and strength training were differently impacted during the first UK lockdown, with poorer outcomes associated with older age, lower education and higher body mass index. Targeted interventions may be required to avoid pandemic-related inequities in physical activity.

Association between Physical Activity Guidelines and Sedentary Time with Workers' Health-Related Quality of Life in a Spanish Multinational Company

Workers spend a large amount of time working, limiting the possibility of meeting physical activity (PA) guidelines. A better health-related quality of life (HRQoL) provides benefits for the employee and company. The aim of this study was to analyse the associations of four behavioural categories between compliance with PA guidelines (aerobic and strength training) and sedentary time with workers’ HRQoL. We classified the sample into four categories: (1) “Physically active & low sedentary”, (2) “Physically active & high sedentary”, (3) “Physically inactive & low sedentary”, and (4) “Physically inactive & high sedentary”. Student’s t-tests for two independent samples and a multiple linear regression adjusted for covariates were performed. A total of 1004 employees of the multinational company Grupo Red Eléctrica participated. Compliance with PA guidelines and a low level of sedentarism were associated with higher HRQoL (p < 0.001). Compared to “physically inactive & high sedentary”, “physically active & low sedentary” and “physically active & high sedentary” workers obtained a better HRQoL (B = 5.47; p = 0.006 and B = 4.10; p = 0.003; respectively). In this sample of Spanish workers, being physically active was associated with a better HRQoL, even in those with high sedentary time. Experimental studies are needed to confirm our results.

Who is meeting the strengthening physical activity guidelines by definition: A cross-sectional study of 253 423 English adults?

The current UK physical activity guidelines recommend that adults aged 19 to 65 years perform activity to strengthen muscle and bone a minimum of twice weekly. The number of adults meeting strengthening activity guidelines is lower than for aerobic activity, but estimates vary between studies partly due to differences in how muscle-strengthening activity is defined. We aimed to provide estimates for strengthening activity prevalence in English adults based on a nationally representative sample of n = 253,423 18-65-year-olds. We attempted to quantify the variation in estimates attributable to differences in the way strengthening activity is defined. Finally, we aim to provide a brief descriptive epidemiology of the factors associated with strengthening activity. Adults met guidelines for aerobic activity if they reported the activity equivalent to >150 min/week moderate-intensity exercise. Respondents met strengthening guidelines if they reported at least two bouts per week of strengthening activity. We defined strengthening activity, first, according to criteria used in the Health Survey for England (HSE). Second, we counted bouts of strengthening activities for which we could find evidence of health-related benefits (Evidence). Third, we included bouts of strengthening activity as defined in current UK physical activity guidelines (Guideline). Two-thirds (67%) of adults met guidelines for aerobic activity (69% of men, 65% of women). Less than one-third (29% of men and 24% of women) met guidelines for the HSE definition of strengthening activity. Under the Evidence definition, 16% of men and 9% of women met strengthening guidelines. Using the most-stringent definition (Guideline) just 7.3% of men and 4.1% of women achieved the recommendations for strengthening activity. We found females and older adults (50–65 years) were less likely to meet guidelines for aerobic, strengthening, and combined aerobic plus strengthening activity. The prevalence of meeting activity guidelines was lower in adults from more deprived areas (compared with the least deprived); Adults with lower academic qualifications (Level 1) were less likely to meet activity guidelines than those educated to Level 4 (Degree Level) or higher. Having a limiting disability was associated with a lower prevalence of meeting activity guidelines. Associations between socio-demographic measures and the prevalence of adults meeting activity guidelines were stronger for strengthening activity than for aerobic 51(or combined aerobic plus strengthening) activity Compared with aerobic activity, fewer adults engage in strengthening activity regardless of how it is defined. The range in estimates for how many adults meet strengthening activity guidelines can be explained by variations in the definition of ‘strengthening’ that are used and the specific sports or activities identified as strengthening exercise. When strengthening activity is included, the proportion of English adults meeting current physical activity guidelines could be as high as 1 in 3 but possibly as low as just 1 in 20. A harmonized definition of strengthening activity, that is aligned with physical activity guidelines, is required to provide realistic and comparable prevalence estimates.

Association of occupation with the daily physical activity and sedentary behaviour of middle-aged workers in Korea: a cross-sectional study based on data from the Korea National Health and Nutrition Examination Survey

OBJECTIVES

The WHO recommends that adults engage in regular moderate-to-vigorous physical activities (MVPAs) and muscle-strengthening activities (MSA), and minimise sedentary behaviour. This study aimed to determine the association of occupation with MVPA, MSA and sedentary behaviour in middle-aged Korean workers.

DESIGN AND SETTING

A cross-sectional study using data from the seventh Korea National Health and Nutrition Examination Survey (2016-2018).

PARTICIPANTS

Workers aged between 40 and 69 years in Korea (n=6359).

OUTCOME MEASURES

Population-weighted proportions not meeting the MVPA (＜150 min/week) and MSA (＜2 days/week) guidelines, and with high sedentary behaviour (＞7 hours/day) were calculated, and their associations with sociodemographic and work-related variables were assessed using multiple logistic regression analyses. Additionally, the estimated time spent on MVPA, MSA and sedentary behaviour according to the occupation categories (white-collar, pink-collar and blue-collar) was calculated using analysis of covariance (ANCOVA).

RESULTS

The MVPA level did not show a significant difference across the occupation categories. Blue-collar workers showed significantly lower MSA participation than white-collar and pink-collar workers (male, p=0.006; female, p=0.004; by ANCOVA). High sedentary behaviour was significantly associated with white-collar occupations (p<0.001 by ANCOVA). Longer working hours were negatively associated with MVPA (OR=1.01, 95% CI 1.01 to 1.02) and MSA (OR=1.01, 95% CI 1.00 to 1.02). Workers with higher stress were less likely to participate in MSA (male: OR=1.43, 95% CI 1.10 to 1.86; female: OR=1.39, 95% CI 1.08 to 1.80). Self-employed workers showed lower MVPA levels than employees (male: OR=1.26, 95% CI 1.09 to 1.47; female: OR=1.36, 95% CI 1.13 to 1.64). Daily workers compared with full-time workers (OR=0.38, 95% CI 0.24 to 0.59) and temporary workers compared with regular workers (OR=0.75, 95% CI 0.59 to 0.95) were associated with less sedentary behaviour in men.

CONCLUSION

A number of work-related factors were associated with PA levels and sedentary behaviour in middle-aged workers. The workplace is one of the critical elements to intervene in health promotion strategies.

Health-Enhancing Physical Activity in Europe-Combined Aerobic Physical Activity and Muscle-Strengthening Exercise Guideline Adherence Among 280,605 Adults From 28 European Countries

BACKGROUND

Compared with engaging in aerobic physical activity (aerobic PA; eg, walking, running, cycling) or muscle-strengthening exercise (MSE; eg, weight/resistance training) alone, epidemiological evidence suggests that combining both is linked to better health. However, the assessment of both PA modes is rare in health surveillance. This article provides the first multicountry study on the descriptive epidemiology of combined moderate to vigorous PA-MSE guideline adherence.

METHODS

Data were drawn from the European Health Interview Survey wave 2 (2013-2014), comprising samples from 28 European countries (n = 280,605). Self-reported aerobic PA and MSE were assessed using the validated European Health Interview Survey Physical Activity Questionnaire. The authors calculated the weighted proportions meeting the health-enhancing PA guideline (aerobic PA ≥ 150 min/wk and MSE ≥ 2 sessions/wk). Poisson regression assessed the prevalence ratios for meeting the combined guideline across sociodemographic factors and by country.

RESULTS

A total of 15.0% met the health-enhancing PA guideline. The lowest prevalence was from respondents from Southern and Central European countries (Romania, Poland, and Croatia, range: 0.5%-5.7%). Poorer self-rated health, older age, lower income, being female, and being obese had a lower likelihood of meeting the combined guideline.

CONCLUSIONS

Most European adults do not meet the health-enhancing PA guideline that includes both aerobic PA and MSE.

Evaluating the reach, effectiveness, adoption, implementation and maintenance of the Resistance Training for Teens program

BACKGROUND

Physical activity guidelines recommend young people engage in regular muscle-strengthening activities (e.g., resistance training [RT]). However, few school-based physical activity interventions have been delivered at-scale or promoted RT. The aim of this study was to evaluate the reach, effectiveness, adoption, implementation and maintenance of the Resistance Training for Teens (RT for Teens) program.

METHODS

Data were collected between August 2015 and October 2020. RE-AIM was operationalized as: (i) Reach: number and characteristics of students estimated to be exposed to the program; (ii) Effectiveness: impact of the program on student-level outcomes measured in a subsample of 750 students from 17 schools; (iii) Adoption: number and representativeness of schools with one or more teachers trained to deliver the program; (iv) Implementation: extent to which the program was delivered as intended; and (v) Maintenance: extent to which the program was sustained in schools.

RESULTS

The estimated program reach was ~ 10,000 students, out of a total student population of ~ 200,000 (~ 5%). Students were from diverse socioeconomic and ethnic backgrounds. Improvements in muscular fitness, RT self-efficacy, perceived cardiorespiratory fitness and flexibility, and participation in muscle-strengthening physical activities were documented. A total of 30 workshops were delivered, involving 468 teachers from 249 schools from diverse geographical regions. Implementation varied considerably, with teachers adapting the program to suit the context of their school and student cohorts. However, RT skill development and the promotion of muscular fitness were the session components delivered most during sessions. Teachers' adherence to the SAAFE (Supportive, Active, Autonomous, Fair and Enjoyable) teaching principles was high. Approximately 30% of teachers (144/476) registered to use the RT for Teens app. At the school-level, 37% (93/249) of schools had at least one registered user (teacher and/or student). A total of 2,336 workouts and 3,116 fitness tests were completed by registered users. Of the 249 schools represented, 51 (20.5%) sent an additional (previously untrained) teacher to a second workshop.

CONCLUSIONS

The RT for Teens program had broad reach and adoption. However, intervention delivery varied considerably across schools and additional support strategies are required to optimize intervention implementation and maintain program delivery over time. Future studies will benefit from the utilization of accepted frameworks, recommendations and guidelines for implementation research.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12621000352808), retrospectively registered 1^st February 2021.

Prevalence and Correlates of Muscle-Strengthening Activity Participation in Croatia: A Cross-Sectional Study in a National Representative Sample of 4561 Adults

The World Health Organization recommends adults to engage in muscle-strengthening activity (MSA) at least two times per week. The aim of this study was to determine the prevalence and correlates of MSA in Croatian adults. We analysed self-reported data collected among 4561 Croatians aged ≥18 years within the European Health Interview Survey (EHIS wave 2). We calculated the weighted prevalence of meeting the MSA guidelines, and odds ratios for different population groups, adjusted for a range of sociodemographic and lifestyle variables in a multivariable logistic regression analysis. The prevalence of meeting the MSA guidelines was 8.0% (95% CI: 7.2, 8.8) in the overall sample, 5.4% (95% CI: 4.5, 6.4) among females, and 10.9% (95% CI: 9.6, 12.3) among males. We found significantly lower odds of meeting the MSA guidelines for females, older age groups, inhabitants of sparsely populated areas, those with a low education level, obese individuals, and those who did not rate their health as “very good” (p < 0.05 for all). The vast majority of Croatian adults do not meet the MSA guidelines. Public health initiatives to promote MSA in Croatia should focus on females, seniors, sparsely populated areas, people with low education, obese individuals, and those with impaired health.

The epidemiology of muscle-strengthening activity among adolescents from 28 European countries

AIMS

This study aimed to describe the prevalence and socio-demographic and lifestyle-related correlates of muscle-strengthening activity (MSA; strength/resistance training, sit-ups/push-ups, etc.) among a large sample of European adolescents.

METHODS

Data were drawn from the European Health Interview Survey Wave 2 (2013-2014), including 8818 adolescents (15-17 years) from 28 European countries. Self-reported MSA was assessed using a previously validated survey item. Population-weighted prevalence ratios were calculated for (a) 'none' (0 days/week), (b) 'insufficient MSA' (1-2 days/week) or (c) 'sufficient MSA' (⩾3 days/week). Generalised linear models using Poisson regression with robust error variance were used to calculate the prevalence ratios for adolescents reporting sufficient MSA by socio-demographic/lifestyle characteristics and by European region.

RESULTS

Overall, 19.4% (95% confidence interval (CI) 18.3-20.7) reported sufficient (⩾3 days/week) MSA and 57.9% (95% CI 56.4-59.6) reported none. Females, adolescents from Southern and Eastern European regions, those not meeting the aerobic guideline and adolescents classified as overweight were significantly associated with a lower likelihood of reporting sufficient MSA, independent of other characteristics.

CONCLUSIONS

The majority of European adolescents do not meet the MSA guidelines. Future large-scale MSA public-health interventions should target female and currently inactive adolescents, as well as those from Southern and Eastern European regions.

Community-Based Survey Exploring Use of the Dietary Supplement Creatine by Adult Non-Athletes

Creatine is classified as a “sports supplement”, but it also has health benefits. The purpose of this study was to assess use of creatine as a dietary supplement in adult non-athletes. Three hundred ninety-nine adults (19–89 years) completed an online survey. Among the respondents, 77% (n = 307) were regularly active, including participation in weightlifting (34%), running (34%), and cycling (21%). Twenty-eight percent (n = 111) reported use of creatine with an average dose of 6.4 ± 4.5 g. Daily creatine use was reported by 45%, and 38% reported using creatine 2–6 times weekly. Primary sources of information about creatine were trainers/coaches (29%), friends/family (32%), and internet (28%). Forty percent (n = 44) of creatine users were female. When compared by age, 46% of young, 32% of midlife, and 6% of old respondents reported creatine use with no differences in dose or frequency. Young and midlife respondents reported primarily trainers/coaches, friends/family, and internet as sources of information about creatine, but old respondents limited their sources to friends/family and fitness magazines. Although creatine is widely used by adult non-athletes who regularly exercise, dietitians and other healthcare providers are not the primary source of information. Fitness trainers can appropriately provide guidance and education regarding safe and effective use of creatine.

Associations between physical activity types and multi-domain cognitive decline in older adults from the Three-city cohort

Several studies suggest that physical activity improves cognitive functions and reduces cognitive decline, whereas others did not find any evidence of a neuroprotective effect. Furthermore, few cohort studies have analyzed the different physical activity types and particularly household activities. Our objective was to assess the association of two physical activity types with the decline in different cognitive domains in a large prospective cohort of community-dwelling older adults from the Three-city study. Physical activity (domestic/transportation activities and leisure/sport activities) was assessed with the Voorrips questionnaire, specific for older adults. Baseline sociodemographic and health history variables as well as cognitive performance data at baseline and during the 8-year follow-up (Mini-Mental State Examination, Benton Visual Retention Test, Trail Making Tests A and B, Isaac's Set Test and Free and Cued Selective Reminding Test) were also available. Associations between physical activity scores and cognitive decline in different domains were tested using minimally- and multi-adjusted linear mixed models. The analysis included 1697 participants without dementia at baseline and with at least one follow-up visit. At baseline, participants with higher sub-scores for the two physical activity types had better cognitive performances. Interaction with time showed that decline in some cognitive scores (Trail Making Test B and Isaac's Set Test) was significantly less pronounced in participants with higher household/transportation activity sub-scores. No significant effect over time was found for leisure/sport activities. This study shows that during an 8-year follow-up, executive functions and verbal fluency were better preserved in older adults who performed household/transportation activities at moderate to high level. Participation in domestic activities and using adapted transport means could allow older adults to maintain specific cognitive abilities.

The Development Strategy of Home-Based Exercise in China Based on the SWOT-AHP Model

In view of the increasing importance of sports to people and the impact of COVID-19 on people’s lives, home-based exercise has become a popular choice for people to keep fit due to its unique advantages and its popularity is expected to keep growing in the future. Therefore, it is necessary to determine the development direction of home-based exercise and put in the corresponding efforts. However, there is currently a lack of research on all aspects of home-based exercise. The purpose of this research was to investigate the effective sustainable development strategy of home-based exercise in China through a SWOT (Strengths, Weaknesses, Opportunities and Threats) and AHP (Analytic Hierarchy Process) hybrid model. Thirteen factors corresponding to the SWOT analysis were identified through a literature review and expert opinions. The results show that in China the advantages and potential outweigh the weaknesses and threats of home-based exercise. Home-based exercise should grasp the external development opportunities and choose the SO development strategic type that combines internal strengths and external opportunities. As the core for the development of home-based exercise, this strategy should be given priority. To sum up, home-based exercise is believed to have a bright future.

Effects of Creatine Supplementation on Properties of Muscle, Bone, and Brain Function in Older Adults: A Narrative Review

Aging is associated with reductions in muscle and bone mass and brain function, which may be counteracted by several lifestyle factors, of which exercise appears to be most beneficial. However, less than 20% of older adults (> 55 years of age) adhere to performing the recommended amount of resistance training (≥ 2 days/week) and less than 12% regularly meet the aerobic exercise guidelines (≥ 150 min/week of moderate to vigorous intensity aerobic exercise) required to achieve significant health benefits. Therefore, from a healthy aging and clinical perspective, it is important to determine whether other lifestyle interventions (independent of exercise) can have beneficial effects on aging muscle quality and quantity, bone strength, and brain function. Creatine, a nitrogen containing organic compound found in all cells of the body, has the potential to have favorable effects on muscle, bone, and brain health (independent of exercise) in older adults. The purpose of this narrative review is to examine and summarize the small body of research investigating the effects of creatine supplementation alone on measures of muscle mass and performance, bone mineral and strength, and indices of brain health in older adults.

Engagement in Muscle-Strengthening Activities Lowers Sarcopenia Risk in Older Adults Already Adhering to the Aerobic Physical Activity Guidelines

Sarcopenia in older adults is associated with a higher risk of falls, disability, loss of independence, and mortality. Current physical activity (PA) guidelines recommend engagement in muscle-strengthening activities (MSA) in addition to aerobic moderate-to-vigorous physical activity (MVPA). However, little is known about the impact of MSA in addition to adherence to the MVPA recommendation in the guidelines. The aim of the present cross-sectional study was to determine whether or not engagement in MSA is linked to sarcopenia risk in older adults who meet the PA guidelines of 150 min of MVPA per week. A total of 193 community-dwelling older men and women (65–70 years) were included in the study. A continuous sex-specific clustered sarcopenia risk score (SRS) was created based on muscle mass assessed using bioelectrical impedance analysis, handgrip strength, and five times sit-to-stand (5STS) time, assessed using standardized procedures. Adherence to PA guidelines was assessed using the Actigraph GT3x accelerometer and the EPAQ2 questionnaire. Guideline adherence to MSA twice a week was related to a significantly (p < 0.05) lower SRS compared to those who did not. This finding was evident after adjustment for adherence to the protein intake guideline and abdominal obesity. Similar impacts were observed for muscle mass and 5-STS but not for handgrip strength. In conclusion, guideline adherence to MSA is related to lower sarcopenia risk in older adults who already accumulate 150 weekly minutes of MVPA, which reinforces the promotion of the MSA guideline, alongside the MVPA guideline, to fight against sarcopenia progression in ageing populations.