Sedentary Behaviour and Fall-related Injuries in Aging Adults: Results from the Canadian Longitudinal Study on Aging (CLSA).

Background: Falls, and more specifically, fall-related injuries, are costly to the healthcare system and can harm one's autonomy. Objectives: To study the impact of sedentary behaviour associated with fall-related injuries and how a change in sedentary behaviour may impact the risk of a fall-related injury. Design: From baseline to the first follow-up, cross-sectional and longitudinal data analysis from the Canadian Longitudinal Study of Aging (CLSA) cohort. Participants: CLSA data from 43,558 Canadians aged 45-85 were included in this study. Measurements: At baseline and follow-up, sedentary behaviour time was categorized as low (<1,080 minutes/week), moderate (1,080-1,440), or high (>1,440). Sedentary behaviour was estimated via the Physical Activity Scale for the Elderly (PASE). At follow-up, participants were dichotomized as either increased or decreased/no change in sedentary behaviour according to their categorical change between time points. Results: Sedentary behaviour was associated with fall-related injuries independently of age, sex, number of chronic conditions, and total physical activity levels OR (95%CI) 1.10 (1.05-1.15). In contrast, a change in sedentary behaviour was not associated with the risk of fall-related injury 1.00 (0.92-1.01). Conclusion: A higher level of sedentary behaviour is associated with injurious falls for people between 40 and 80 years old. However, a short-term change in sedentary behaviour does not influence the risk of injury-related falls. Despite the results, a more precise measure of sedentary behaviour is needed for epidemiology studies to capture changes over time better.

Validity of common physical function tests performed online for older adults.

BACKGROUND: Objectively measured physical function tests are important predictors of institutionalization, disability, and premature mortality. Although physical function was usually assessed in person prior to the COVID-19 pandemic, there is a need to investigate whether physical function tests performed online are valid. OBJECTIVE: The purpose of this study was to determine the validity of common physical function tests conducted online compared to in-person testing in older adults. METHODS: Physical functions included gait speed, one leg stance balance, 30-second chair stands, and the 2-minute steps were tested online and in-person using a random order for community dwellers aged 65 years and above. Using an alpha two way mixed model, average intraclass correlation coefficients (ICC) were calculated between the two settings and one sample T-test performed on the difference between the results of each test between the two settings. Finally, Bland-Altman plots were created, and proportional biases tested via linear regressions. RESULTS: Besides the one-leg stance balance with eyes closed, for which the ICC was 0.47 (0.23-0.74) the average ICC's were excellent ranging from 0.87 to 0.94. No proportional biases were observed based on Bland-Altman graphs. CONCLUSION: For older adults living in the community, common physical function tests can be performed online.

Nutrition and Physical Activity Clinical Practice Guidelines for Older Adults Living with Frailty.

BACKGROUND: We developed clinical practice guidelines to provide health care providers with evidence-based recommendations for decisions related to the effective management of frailty and pre-frailty using nutrition and physical activity interventions. METHODS: We based the recommendations on two systematic reviews with meta-analyses. Nutrition, physical activity, and combined nutrition and physical activity interventions for adults ≥65y were considered if study populations were identified as frail using a frailty tool or assessment. Risk of bias and certainty of evidence were evaluated. We included physical outcomes, mobility, frailty, cognitive function, activities of daily living, falls, quality of life, diet quality, energy/fatigue levels, health services use, and caregiver outcomes. RESULTS: Overall, mobility improvements were moderate with nutritional strategies that optimize dietary intake, various types of physical activity interventions, and interventions that combine nutrition and physical activity. Physical outcomes, such as body mass and muscle strength, improved moderately with nutritional strategies and interventions that combined nutrition with physical activity. Frailty status improved with multi-component physical activity interventions. Strong recommendations include optimizing dietary intake, performing physical activity, and adopting interventions that combine nutrition and physical activity. We strongly recommend various types of physical activity including muscle strengthening activities, mobilization or rehabilitation exercises, and multi-component physical activity interventions. INTERPRETATION: Tailored nutrition and physical activity interventions based on individual goals and health status are associated with improved clinical and physical outcomes. While the recommendations facilitate shared decision-making, we identified sparse application of validated frailty assessments and lack of standardized research outcomes as critical gaps in knowledge.

Peer-led exercise program for ageing adults to improve physical functions - a randomized trial.

BACKGROUND: A peer-led exercise program is one way to empower people sharing similar characteristics to encourage others to be active, but there is a lack of evidence that these programs have physical function and other benefits when delivered to ageing adults. METHODS: This randomized controlled trial lasting 12 weeks proposed an exercise peer-led program offered to 31 adults aged 50 and above, twice a week, by a trained leader of the same age from March to May 2019. The program was offered for free with limited space and equipment. Valid tests of physical function (e.g., 30-s chair stand, 6-min walk test) were used to assess the functional benefits. Psychosocial outcomes were assessed using self-reported questionnaires and metabolic outcomes via a fasted blood draw. RESULTS: A significant difference was found between pre-and post-values in most physical function tests in the intervention group (all p < 0.05). When adjusted for potential confounders, the intervention group was significantly associated with a more significant improvement on the chair stand test (ß = .26; p < 0.001; r2 = 0.26), the arm curl (ß = .29; p < 0.001; r2 = 0.49), as well as the 6-min walk test (ß = -.14; p < 0.001; r2 = 0.62) compared with the control group. Using repetitive measures generalized linear model, the interaction between the changes and the group was significant for all three tests. Benefits were also observed for participants' stress level and perceived health in the intervention group compared to the control. Finally, no significant difference was observed between groups for metabolic health. CONCLUSIONS: The current work suggests that a 12-week peer-led exercise program can improve physical function for adults age 50 and above. TRIAL REGISTRATION: NCT03799952 (ClinicalTrials.gov) 12/20/2018.

Is sitting time leading to mobility decline in long-term care residents?

BACKGROUND: Little is known about the sitting time in long-term care (LTC) facilities, or if sedentary behaviour affects changes in mobility over time. AIMS: The objectives were to document the sitting time of LTC residents and to examine if sitting time could predict changes in mobility. METHODS: Twenty residents of an LTC facility, representing three mobility statuses (independent, assisted transfer, and dependent transfer) were included. Sitting time was defined using an ActivPAL. Mobility statuses were reviewed 12 months later. RESULTS: Participants spent an average of 21.9 h per day sedentary. At follow-up, five residents experienced a decline in mobility status, but no baseline sitting time variables were associated with the changes in mobility status (P > 0.05). DISCUSSION/CONCLUSION: People living in LTC are highly sedentary. Sitting time differs amongst the mobility statues, but is unable to predict upcoming changes in mobility status.

Effect of an acute exercise bout on immediate post-exercise irisin concentration in adults: A meta-analysis.

Irisin is a recently discovered myokine that increases adipocyte metabolism, induces further "browning" of white adipose tissue, and enhances glucose metabolism. No study has ever determined how an acute bout of exercise impacts immediate post-exercise irisin concentration using a meta-analytic approach. The purpose of this study is to determine the impact of an acute bout of exercise on the magnitude of post-exercise irisin concentration in adults using meta-analytic procedures. Searches were performed on PubMed, EMBASE, CINAHL, PEDro, SCOPUS, and SPORTDiscus databases. Effect summaries were obtained using random-effects models. Random-effects single and multiple meta-regressions were performed to determine relationships between, and potential confounding effects of, variables of interest. Ten articles were retained for the final meta-analysis, producing 21 study estimates. An acute bout of exercise was accompanied by a post-exercise average increase in irisin concentration of 15.0 (95% CI: 10.8%-19.3%). There was no significant relationship between post-exercise irisin concentration and age, intensity of aerobic exercise, or type of exercise training session (resistance vs aerobic training). Fitness level and body mass index were identified as significant predictive variables for post-exercise irisin concentration. However, a multiple meta-regression model identified fitness level as the single best predictor, with being fit (21.1%±2.2%) associated with a nearly twofold increase in post-exercise irisin concentration, compared with being unfit (11.8%±2.1%). Immediately following an acute bout of exercise, irisin concentration increases substantially in adults, with fitness level as an important modifier for the effect.

Walking Cadence to Exercise at Moderate Intensity for Adults: A Systematic Review.

Background. Most adults choose walking as a leisure activity. However, many do not reach the international physical activity guidelines for adults, which recommend moderate intensity aerobic activity for at least 150 minutes/week in bouts of 10 minutes. Purpose. This systematic review provides an update on the walking cadence required to reach moderate intensity in adults and older adults, identifies variables associated with reaching moderate intensity, and evaluates how walking cadence intensity should be measured, but the main purpose is to report the interventions that have been attempted to prescribe walking cadence to increase time spent at moderate intensity or other outcomes for adults and older adults. Methods. SportDISCUS, Scopus, and PubMed databases were searched. We identified 3,917 articles and 31 were retained for this systematic review. Only articles written in English were included. Results. In general, 100 steps/minute is prescribed for adults to achieve moderate intensity, but older adults may require a higher cadence. Currently, few studies have explored using walking cadence prescription as an intervention to increase physical activity levels. Conclusion. Prescribing walking cadence as a way to increase physical activity levels has potential as a practical and useful strategy, but more evidence is required to assess its ability to increase physical activity levels at moderate intensity.

Weight gain since menopause and its associations with weight loss maintenance in obese postmenopausal women.

OBJECTIVE: To examine the association between weight gain since menopause and weight regain after a weight loss program. METHODS: Participants were 19 obese women who participated in a 15-week weight loss program and a 12-month follow-up. Main outcomes were: body composition, resting metabolic rate, energy intake, energy expenditure, and weight regain at follow-up. RESULTS: All body composition measures significantly decreased after intervention (all P ≤ 0.01) while all measures of fatness increased significantly after the 12-month follow-up (P ≤ 0.01). Body weight gain since menopause was associated with body weight regain (r = 0.65; P = 0.003) after follow-up even after adjustment for confounders. CONCLUSION: Weight gain since menopause is associated with body weight regain following the weight loss program. Therefore, weight gain since menopause should be considered as a factor influencing weight loss maintenance in older women.

Relative strength as a determinant of mobility in elders 67-84 years of age. a nuage study: nutrition as a determinant of successful aging.

This cross-sectional study proposes two relative strength indexes in order to evaluate the risks of lower mobility in healthy older adults: 1) handgrip strength on body mass index and 2) quadriceps strength on body weight. Nine hundred and four men and women aged between 67-84 years old were tested for body composition, muscle strength and mobility function. Individuals in the lowest and middle tertiles of relative handgrip strength were respectively 2.2 (1.3-3.7) and 4.4 (2.6-7.6) more likely to have a lower mobility score. As for relative quadriceps strength, odd ratios for lowest and middle tertiles were respectively 2.8 (1.6-4.9) and 6.9 (3.9-12.1). Relative strength indexes, either using handgrip strength or quadriceps strength, are convenient to use in large scale studies and clinical practice.

Estimation of energy expenditure in a work environment: comparison of accelerometry and oxygen consumption/heart rate regression.

The aim of this study was to compare estimation of energy expenditure (EE) in working environments, either from accelerometry or from an individual oxygen consumption/heart rate (VO(2)/HR) regression curve. The study participants were 46 volunteer workers aged 27+/-6 years old. A significant correlation between EE predicted by the VO(2)/HR curve and the accelerometer was observed (r=0.78, p <0.01). However, more disparities were observed between the two methods when the mean job intensity was not within 16% and 23% higher than resting HR. The accelerometer overestimated by a mean of 34.4% the prediction by VO(2)/HR regression if the intensity of the task was lower than a total of 1000 kcal/shift and underestimated the prediction by a mean of -24.9% if EE estimation of the work shift was higher than a total of 1500 kcal/shift. Despite a high correlation between both methods in the whole group, EE evaluated by accelerometry does not correspond to EE predicted by the VO(2)/HR regression curves when evaluated individually.