The Effects of High- Versus Low-Intensity Power Training on Muscle Power Outcomes in Healthy, Older Adults: A Systematic Review.

Power training (PT) improves muscle power in older adults; however, intensity recommendations are less clear. A narrative approach was used to compare high- versus low-intensity PT on muscle power (and function) in healthy, older adults. Searches were performed using Medline, Embase, CINAHL, SPORTDiscus, AgeLine, and Scopus. Interventions in which older subjects (60+ years) were instructed to perform the concentric phase "as fast as possible" were included. After searches were performed, a third category of PT (moderate intensity) was included. Evidence from 27 studies (32 PT groups) showed changes in muscle power that averaged 26.8%, 33.4%, and 21.5% for high-, moderate-, and low-intensity PT, respectively, with greater changes with longer training duration and in mildly mobility-limited older adults. Function improved similarly across categories. In conclusion, both low- and high-intensity PT led to clinically significant changes in power and are viable options for improving power and function in older adults.

Development of a physical literacy model for older adults - a consensus process by the collaborative working group on physical literacy for older Canadians.

BACKGROUND: Arguably the uptake and usability of the physical activity (PA) guidelines for older adults has not been effective with only 12% of this population meeting the minimum guidelines to maintain health. Health promoters must consider innovative ways to increase PA adoption and long-term sustainability. Physical literacy (PL) is emerging as a promising strategy to increase lifelong PA participation in younger age-groups, yet there is relatively little evidence of PL being used to support older adults in achieving the PA guidelines. METHODS: An iterative and mixed-methods consensus development process was utilized over a series of six informed processes and meetings to develop a model of physical literacy for adults aged 65 years and older. RESULTS: A multi-disciplinary collaborative working group (n = 9) from diverse practice settings across Canada, and representative and reflective of the full range of key elements of PL, was assembled. Three consensus meetings and two Delphi surveys, using an international cohort of 65 expert researchers, practitioners, non-government organizations and older adults, was conducted. 45% responded on the first round and consensus was achieved; however, we elected to run a second survey to support our results. With 79% response rate, there was consensus to support the new PL model for older adults. CONCLUSION: Older adults are a unique group who have yet to be exposed to PL as a means to promote long-term PA participation. This new PL model uses an ecological approach to integrate PL into the lifestyles of most older adults. Understanding the interactions between components and elements that facilitate PL will ultimately provide a new and effective tool to target PA promotion and adherence for all older Canadians.

Perceptions of exercise screening among older adults.

Prephysical activity screening is important for older adults' participating in physical activity. Unfortunately, many older adults face barriers to exercise participation and thus, may not complete proper physical activity screening. The purpose of this project was to conduct a thematic analysis of perceptions and experiences of community-dwelling older adults regarding prephysical activity screening (i.e., Get Active Questionnaire (GAQ) and a standardized exercise stress test). A convenience sample of adults (male n = 58, female n = 54) aged 75 ± 7 years living in the City of London, Ontario, Canada, was used. Participants completed a treadmill stress test and the GAQ at a research laboratory for community-based referrals. One week later, participants completed the GAQ again and were asked questions by a research assistant about their perceptions of the screening process. Thematic analysis of the responses was conducted. The results indicated that older adults view physical activity screening as acceptable, but not always necessary. Also, the experiences expressed by this sample of older adults indicated that physical activity screening can contribute to continued confidence (through reassurance) and can contribute to increased motivation (through yearly fitness results) in exercise participation. In conclusion, older adults may perceive screening as supportive in exercise adoption, if screening is simple, convenient, and supports older adults' motivation and confidence to exercise.

Long-term Evaluation of the "Get Fit for Active Living" Program.

This study examined six- and 12-month levels of adherence to physical activity, functional changes, and psychosocial determinants of physical activity in 176 older adults who participated in the "Get Fit for Active Living (GFAL)" pilot program. Functional and psychosocial measures were conducted in person at six months; psychosocial measures and physical activity participation were assessed by telephone interview at 12 months. Ninety-five per cent were retained in the study at the six-month follow-up, and 88 per cent at 12 months. The self-reported adherence rate to exercise at 12 months was 66 per cent. The main reason for continued exercise participation was to maintain health (45%). Reasons for nonadherence were illness (38%) and lack of motivation (32%). Results identify factors associated with positive behaviour change that health promoters can utilize when targeting the older adult population. The GFAL project results can serve as a model for sustainable, community-based older-adult exercise programs.

Letter to the Editor: Can Older Adults "Walk" Their Way to Successful Aging? The Case for Physical Activity Literacy for an Aging Population.

No abstract available for this article.

Exercise Modality Choices One Year After Intervention in Previously Inactive Older Men and Women.

A convenience sample of 176 healthy, community-dwelling, inactive older adults (mean age 70 ± 5 years; 62 males, 114 females) were tracked for one year. The purpose was to describe the exercise modality choices older adults make one year following participation in an exercise and education intervention. Telephone follow-up contacted 137 participants (78%, men = 50, women = 87) and 62% of the men and 69% of the women reported to be "currently exercising." Exercising independently was the most common type of exercise reported by 81% and 64% of men and women, respectively. Walking was the most commonly reported modality by both genders. The setting of exercise was most often reported to be at home or outside for both men and women. The main reason for continued participation at 12 months was for overall health (50% of men and 40% of women). Little variation was observed for exercise modality choice. Future interventions should consider a variety of exercise and physical activity opportunities for older adults.

Recommendations for a core outcome set for measuring standing balance in adult populations: a consensus-based approach.

BACKGROUND: Standing balance is imperative for mobility and avoiding falls. Use of an excessive number of standing balance measures has limited the synthesis of balance intervention data and hampered consistent clinical practice. OBJECTIVE: To develop recommendations for a core outcome set (COS) of standing balance measures for research and practice among adults. METHODOLOGY: A combination of scoping reviews, literature appraisal, anonymous voting and face-to-face meetings with fourteen invited experts from a range of disciplines with international recognition in balance measurement and falls prevention. Consensus was sought over three rounds using pre-established criteria. DATA SOURCES: The scoping review identified 56 existing standing balance measures validated in adult populations with evidence of use in the past five years, and these were considered for inclusion in the COS. RESULTS: Fifteen measures were excluded after the first round of scoring and a further 36 after round two. Five measures were considered in round three. Two measures reached consensus for recommendation, and the expert panel recommended that at a minimum, either the Berg Balance Scale or Mini Balance Evaluation Systems Test be used when measuring standing balance in adult populations. LIMITATIONS: Inclusion of two measures in the COS may increase the feasibility of potential uptake, but poses challenges for data synthesis. Adoption of the standing balance COS does not constitute a comprehensive balance assessment for any population, and users should include additional validated measures as appropriate. CONCLUSIONS: The absence of a gold standard for measuring standing balance has contributed to the proliferation of outcome measures. These recommendations represent an important first step towards greater standardization in the assessment and measurement of this critical skill and will inform clinical research and practice internationally.

Correlates of extended sitting time in older adults: an exploratory cross-sectional analysis of the Canadian Community Health Survey Healthy Aging Cycle.

OBJECTIVES: Sitting time has been identified as an independent predictor of health; however, little is known of the determinants of extended sitting time among older adults. The purpose of this study was to identify potential sociodemographic, physical environment, health-related and psychosocial correlates of extended sitting time among older adults living independently in the community. METHODS: Data from adults over the age of 65 from the Canadian Community Health Survey (Healthy Aging Cycle, 2008-2009) were used for analysis (n = 14,560). Self-reported sitting time (<4 or ≥4 h/day) was the main outcome. RESULTS: Age, retirement status, dwelling type, chronic disease, perceived health, body mass index, mood disorder and sense of belonging to community were associated with sitting for 4 or more hours/day. Very low, but not low or moderate, physical activity (OR 1.43; CI 1.19-1.72) was associated with sitting for 4 or more hours/day when compared to those classified as having high physical activity. CONCLUSIONS: Several specific correlates of extended sitting time were identified among older males and females; these findings have implications for public health strategies targeting older adults.

Flexibility of older adults aged 55-86 years and the influence of physical activity.

Cross-sectional age-related differences in flexibility of older adults aged 55-86 years of varying activity levels were examined. Shoulder abduction and hip flexion flexibility measurements were obtained from 436 individuals (205 men, 71 ± 9 years; 231 women, 72 ± 8 years). Total physical activity was assessed using the Minnesota Leisure-Time Physical Activity Questionnaire. Shoulder abduction showed a significant decline averaging 5 degrees/decade in men and 6 degrees/decade in women. Piecewise linear regression showed an accelerated decline in men starting at the age of 71 years of 0.80 degrees/year, whereas in women the onset of decline (0.74 degrees/year) was 63 years. Men and women showed a significant decline in hip flexion (men: 6 degrees/decade; women: 7 degrees/decade). Piecewise linear regression revealed a rate of decline of 1.16 degrees/year beginning at 71 years in men and in women a single linear decline of 0.66 degrees/year. Multiple regression analysis showed that age and physical activity accounted for only 9% of the variance in hip flexion in women and 10% in men, with age but not physical activity remaining significant. Similarly for shoulder abduction, age was significant but not physical activity, in a model that described 8% of the variance for both sexes.

Physical activity-related injuries in older adults: a scoping review.

The purpose of this project is to conduct a comprehensive and systematic scoping review to identify and document the breadth of literature related to physical activity-related injuries in older adults. The population of interest was adults (both males and females) over the age of 65 years, participating in exercise, leisure-time, or sport-type physical activities. The initial search yielded 16,828 articles, with 43 articles ultimately included. The final 43 articles utilized the following study designs: three experimental (two randomized control and one non-randomized control), 14 prospective studies, and 26 retrospective. The results of this scoping review would suggest that it may be premature to provide definitive incidence rates, causes, and correlates of physical activity-related injuries in older adults. However, the current literature does not suggest that older adults are at an increased risk of injury from participation in physical activities. Future research should utilize a consistent definition of 'injury' and consistent and comprehensive descriptors of injuries--including intensity level of engagement of activity and burden/severity of injury. In addition, injury rates in specific populations are needed, particularly for the oldest-old, for those in assisted-living situations, and for subgroups with clinical conditions. Finally, greater surveillance and documentation of older adult initiatives and interventions are needed in order to identify programs successful in reducing the injury rates of their target populations.

A 12-month incidence of exercise-related injuries in previously sedentary community-dwelling older adults following an exercise intervention.

OBJECTIVES: Fear of injury is reported as a barrier to exercise by older adults. However, the literature is limited in describing exercise injuries in older adults. DESIGN: This study prospectively evaluated the 12-month incidence of exercise-related injuries to community-dwelling older adults (n=167 respondents; 63 men, 104 women; mean age 69±5 year). METHODS: A questionnaire developed for use in older adults was administered to document self-reported injuries. Linear regression analysis was conducted to identify covariates related to injury outcomes. RESULTS: 23 people (14%) reported injuries. 41% of injuries were to the lower extremities, where the most common type was overuse muscle strains (32%, n=7). Overexertion was the most common cause of injury (n=9) and walking accounted for half of the activities during which injury occurred. 70% of injuries required medical treatment. 44% were not able to continue exercising after injury and return-to-activity time varied from 1 to 182 days. Sex, age and exercise volume were not significantly associated with injury occurrence. CONCLUSIONS: These results showed similar, or lower, exercise-related injury rates as compared with previous reports on younger and middle-aged adults; however, the definition of, and criteria for, 'injury' reporting varies in the literature. This study indicates that older adults taking up exercise are not at increased risk of injury versus younger age groups.

Influence of hormone replacement therapy and aerobic exercise training on oxygen uptake kinetics in postmenopausal women.

The purpose of this study was to determine the effects of aerobic exercise training on the adjustment of pulmonary oxygen (O2) uptake (VO2p) kinetics in postmenopausal women in 2 groups: those using hormone replacement therapy (HRT) (HRT group) (n = 7, aged 56 ± 4 years) and those not using HRT (nonHRT group) (n = 8, aged 60 ± 5 years). The influence of training (cycle-ergometer 3 times per week for 6 weeks) on step transitions to both moderate-intensity (80% of the gas exchange threshold) and heavy-intensity (Δ50) cycling exercise was studied. Breath-by-breath VO2p data were collected using a mass spectrometer. There were no differences in baseline characteristics between the HRT and nonHRT groups. Moderate-intensity exercise VO2p kinetics were significantly speeded (p < 0.05) with the τVO2p decreasing from 46 ± 8 s before training to 32 ± 4 s after training. Similarly, during the heavy-intensity exercise, on-transient phase 2 τVO2p was reduced from before training (48 ± 7 s) to after training (38 ± 6 s). The use of HRT did not influence the effect of the endurance exercise training on τVO2p during moderate or heavy exercise in healthy postmenopausal women. To provide insight into the mechanism of adjustment, knee extension exercise was studied, and the VO2p kinetics were significantly speeded (p < 0.05), with the τVO2p of the knee extension exercise decreasing from 62.2 ± 18.3 s before training to 48.0 ± 16.2 s after training. Thus, 6 weeks of exercise training resulted in appreciably faster cycling phase 2 VO2p kinetics during moderate and heavy exercise in older women, independent of HRT use.

Flexibility training and functional ability in older adults: a systematic review.

Background. As indicated in a recent systematic review relating to Canada's Physical Activity Guidelines for Older Adults, exercise interventions in older adults can maintain or improve functional abilities. Less is known about the role of flexibility in the maintenance or improvement of functional abilities, and there currently does not exist a synthesis of the literature supporting a consensus on flexibility training prescription. Purpose. To systematically review the effects of flexibility-specific training interventions on measures of functional outcomes in healthy older adults over the age of 65 years. Methods. Five electronic databases were searched for intervention studies involving concepts related to aging, flexibility, functional outcomes, and training interventions. After evaluating the articles for relevance, 22 studies were considered. Results. The results suggested that while flexibility-specific interventions may have effects on range of motion (ROM) outcomes, there is conflicting information regarding both the relationship between flexibility interventions and functional outcomes or daily functioning. Conclusions. Due to the wide range of intervention protocols, body parts studied, and functional measurements, conclusive recommendations regarding flexibility training for older adults or the validity of flexibility training interventions as supplements to other forms of exercise, or as significant positive influences on functional ability, require further investigation.

Psychometric properties of a questionnaire to assess exercise-related musculoskeletal injuries in older adults attending a community-based fitness facility.

OBJECTIVES: There currently exists no reliable or validated tool for the assessment of exercise-related injuries in older adults. The purpose was to develop and evaluate the psychometric properties of a questionnaire to measure exercise-related injury in older adults participating in supervised exercise programmes. DESIGN: The study utilised a repeated survey design. SETTING: The study took place at one community-based older-adult exercise facility. PARTICIPANTS: The questionnaire was administered to 110 community-dwelling older adults (45 men, mean age 75±8 years; 65 women, mean age 71±8 years). All participants completed the survey at both time points. OUTCOME MEASURES: Test-retest reliability of the self-administered written questionnaire was determined at two-time points. The questionnaire asked participants about their exercise-related injury incurred at the facility in the 12 months. Items included the mechanism, cause and site of injury. The minimum requirement for reliability (κ coefficient) was set at 0.80. RESULTS: 16% (n=18) reported having an injury. Test-retest reliability ranged from 0.76 to 1.00, with all but type of injury (0.76) having κ coefficients greater than 0.80. The lower extremities were the most common site of exercise-related injury. Overexertion movements were the most common cause of injury occurring during strength training exercises. CONCLUSIONS: The present questionnaire assessing the 12-month recall in older adults is a reliable measure of exercise-related injuries and information gained indicates that older adults can safely participate in exercise activities.

Sedentary behavior and physical activity are independent predictors of successful aging in middle-aged and older adults.

Background. Sedentary behavior is emerging as an important risk factor for poor health. Physical activity has proven to be important in determining overall successful aging (SA) among older adults; however, no data exists on the influence of sedentary behavior on SA. The purpose of this analysis was to determine whether there is an association between sedentary behavior and successful aging, independent of physical activity levels. Methods. 9,478 older (M = 4,245; F = 5,233) and 10,060 middle-aged (M = 4.621; F = 5,439) adults from the Healthy Aging cycle of the Canadian Community Health Survey were analyzed. Multivariate logistic regressions were conducted with SA and its three components as outcomes while physical activity and sedentary behavior were entered as main exposures. Results. Among older adults, compared to those who were sedentary (4 hours or more/day), those who were moderately (2-4 hours/day) and least sedentary (<2 hours/day) were 38% (OR: 1.38; CI: 1.12-1.69) and 43% (OR: 1.43; CI: 1.23-1.67) more likely to age successfully, respectively. Among middle-aged adults, those who were least sedentary were 43% (OR: 1.43; CI: 1.25-1.63) more likely to age successfully. Conclusions. These novel findings suggest that sedentary activities are significantly associated with lower odds of SA among middle-aged and older adults, potentially in a dose-dependent manner.

The effectiveness of exercise interventions for the management of frailty: a systematic review.

This systematic review examines the effectiveness of current exercise interventions for the management of frailty. Eight electronic databases were searched for randomized controlled trials that identified their participants as "frail" either in the title, abstract, and/or text and included exercise as an independent component of the intervention. Three of the 47 included studies utilized a validated definition of frailty to categorize participants. Emerging evidence suggests that exercise has a positive impact on some physical determinants and on all functional ability outcomes reported in this systematic review. Exercise programs that optimize the health of frail older adults seem to be different from those recommended for healthy older adults. There was a paucity of evidence to characterize the most beneficial exercise program for this population. However, multicomponent training interventions, of long duration (≥5 months), performed three times per week, for 30-45 minutes per session, generally had superior outcomes than other exercise programs. In conclusion, structured exercise training seems to have a positive impact on frail older adults and may be used for the management of frailty.

Population attributable risk for functional disability associated with chronic conditions in Canadian older adults.

OBJECTIVES: to investigate the population impact on functional disability of chronic conditions individually and in combination. METHODS: data from 9,008 community-dwelling individuals aged 65 and older from the Canadian Study of Health and Aging (CSHA) were used to estimate the population attributable risk (PAR) for chronic conditions after adjusting for confounding variables. Functional disability was measured using activity of daily living (ADL) and instrumental activity of daily living (IADL). RESULTS: five chronic conditions (foot problems, arthritis, cognitive impairment, heart problems and vision) made the largest contribution to ADL- and IADL-related functional disabilities. There was variation in magnitude and ranking of population attributable risk (PAR) by age, sex and definition of disability. All chronic conditions taken simultaneously accounted for about 66% of the ADL-related disability and almost 50% of the IADL-related disability. CONCLUSIONS: in community-dwelling older adults, foot problems, arthritis, cognitive impairment, heart problems and vision were the major determinants of disability. Attempts to reduce disability burden in older Canadians should target these chronic conditions; however, preventive interventions will be most efficient if they recognize the differences in the drivers of PAR by sex, age group and type of functional disability being targeted.

Moderate and heavy oxygen uptake kinetics in postmenopausal women.

The lack of estrogen in postmenopausal women not using hormone replacement therapy (HRT), compared with those using HRT, may reduce submaximal blood flow during exercise and result in an oxygen delivery limitation constraining oxygen uptake (VO(2) have been changed to V in the abstract, but will appear correctly in the body of the paper.) kinetics. The adaptation of pulmonary VO(2) (VO(2p)) during the transition to exercise in older women was examined in this study. Thirty-one healthy postmenopausal women (mean age, 61 +/- 6 years), 15 not using HRT and 16 using HRT, performed repeated exercise transitions (6 min) on a cycle, to work rates corresponding to 80% of estimated ventilatory threshold (moderate-intensity exercise) and to Delta50 (heavy-intensity exercise). There was no difference in moderate-intensity tauVO(2p) between non-HRT (40 +/- 9 s) and HRT (41 +/- 9 s) women. Similarly, there was no difference in heavy-intensity tauVO(2p) between non-HRT (44 +/- 8 s) and HRT (45 +/- 8 s) women. Thus, HRT did not affect the slowing of VO(2) kinetics of older women.

Maximal and submaximal aerobic fitness in postmenopausal women: influence of hormone-replacement therapy.

The purpose of this study was to examine whether maximal and submaximal aerobic fitness parameters (peak oxygen consumption and ventilatory threshold, respectively) are affected by hormone-replacement therapy (HRT) in moderately active postmenopausal women. Forty healthy, active, postmenopausal women (21 taking HRT, mean age 62 +/- 5 years; 19 not taking HRT, mean age 62 +/- 7 years) met the peak oxygen consumption criteria during a cycle ergometer test (15 W ramp) and achieved volitional fatigue. Breath-by-breath measurement was used to determine peak oxygen consumption and to estimate ventilatory threshold. There were no differences in characteristics (age, body mass, height, body mass index, leisure-time physical activity) between the non-HRT and HRT groups, nor were there any differences in responses to maximal exercise, with an observed peak oxygen consumption (mL.kg-1.min-1) of 22.9 +/- 3.8 in the non-HRT group and 22.0 +/- 4.7 in the HRT group. There was also no difference in submaximal aerobic capacity, with ventilatory threshold values (mL.kg-1.min-1) of 16.7 +/- 3.4 in the non-HRT group and 15.6 +/- 3.2 in the HRT group. In a sample of healthy moderately active postmenopausal women, there was no difference in maximal or submaximal aerobic fitness parameters between the HRT and non-HRT groups.

Longitudinal changes in aerobic power in older men and women.

The purpose of this study was to describe the longitudinal (10 yr) decline in aerobic power [maximal O(2) uptake (Vo(2 max))] and anaerobic threshold [ventilatory threshold (T(Ve))] of older adults living independently in the community. Ten years after initial testing, 62 subjects (34 men, mean age 73.5 +/- 6.4 yr; 28 women, 72.1 +/- 5.3 yr) achieved Vo(2 max) criteria during treadmill walking tests to the limit of tolerance, with T(Ve) determined in a subset of 45. Vo(2 max) in men showed a rate of decline of -0.43 ml.kg(-1).min(-1).yr(-1), and the decline in Vo(2 max) was consequent to a lowered maximal heart rate with no change in the maximum O(2) pulse. The women showed a slower rate of decline of Vo(2 max) of -0.19.ml.kg(-1).min(-1).yr(-1) (P < 0.05), again with a lowered HR(max) and unchanged O(2) pulse. In this sample, lean body mass was not changed over the 10-yr period. Changes in Vo(2 max) were not significantly related to physical activity scores. T(Ve) showed a nonsignificant decline in both men and women. Groupings of young-old (65-72 yr at follow-up) vs. old-old (73-90 yr at follow-up) were examined. In men, there were no differences in the rate of Vo(2 max) decline. The young-old women showed a significant decline in Vo(2 max), whereas old-old women, initially at a Vo(2 max) of 19.4 +/- 3.1 ml.kg(-1).min(-1), showed no loss in Vo(2 max). The longitudinal data, vs. cross-sectional analysis, showed a greater decline for men but similar estimates of the rates of change in women. Thus the 10-yr longitudinal study of the cohort of community-dwelling older adults who remained healthy, ambulatory, and independent showed a 14% decline in Vo(2 max) in men, and a smaller decline of 7% in women, with the oldest women showing little change over the 10-yr period.