Age differences in upper extremity joint moments and strength during a laboratory-based tether-release forward fall arrest in older women.

Age-related declines in upper extremity muscle strength may affect an older adult's ability to land and control a simulated forward fall impact. The role of individual upper extremity joints during a forward fall impact has not been examined. The purpose was to evaluate the age differences in upper extremity joint moment contributions during a simulated forward fall and upper extremity muscle strength in older women. A convenience sample of 68 older women (70 (8) yrs) performed three trials of a simulated forward fall. Percentage joint moments of the upper extremity were recorded. Upper extremity muscle strength was collected via handgrip, hand-held dynamometry of the shoulder and elbow and a custom multi-joint concentric and eccentric strength isokinetic dynamometer protocol. Percentage joint moment contributions differed between women in their sixties and seventies with significantly greater relative shoulder joint involvement (P =.008), coupled with lower elbow joint contributions (P =.004) in comparison to 80 year olds. An increase in each year of age was associated with a 4% increase in elbow contribution (Beta = -0.421, r2 = 17.9, P = 0.0001) and a 3.7% decrease in shoulder contribution (Beta = 0.373, r2 = 14.6, P = 0.002). Older women exhibit different landing strategies as they age. Fall injury prevention research should consider interventions focused on these differences taking into account the contributions of upper extremity strength.

Does functional performance and upper body strength predict upper extremity reaction and movement time in older women?

BACKGROUND: Reaction time to initiate upper limb movement and movement time to place hands on the landing surface may be important factors in forward fall landing and impact, contributing to injury reduction. The aim was to investigate the relationship of physical function and upper body strength to upper limb reaction and movement time in older female participants. METHODS: 75 female participants (72 ± 8 yrs) performed 5 arm response trials. Reaction time (signal to initiation of movement), and movement time (initial movement to contact), were collected using 3D motion capture. Additional variables were: handgrip; sit-to-stand; shoulder flexion and elbow extension strength measured by hand-held dynamometry; one-legged balance; fall risk; and physical activity scores. Prediction variables for reaction and movement time were determined in separate backward selection multiple regression analyses. Significance was set at P < 0.05. FINDINGS: Significant regression equations for RT (r2 = 0.08, P = 0.013) found a relationship between stronger handgrip (Beta = -0.002) and faster reaction time, accounting for 8% variance. For movement time (r2 = 0.06, P = 0.036) greater shoulder flexion strength (Beta = -0.04) was related to faster movement time, explaining 6% variance. Stronger SF strength was related to a decrease in MT by 4%. DISCUSSION: A relationship between arm strength measures and faster upper body reaction and movement time was shown, with 10-20% higher strength associated with a 5% faster response time. Even though this was a relatively weak relationship, given that strength is a modifiable component this provides a potential avenue for future intervention efforts. This in turn could have an impact on forward fall landing and potential reduction of injury risk.

Does Fall Arrest Strategy Training Added to a Fall Prevention Programme Improve Balance, Strength, and Agility in Older Women? A Pilot Study.

Purpose: The purpose of this study was to determine the effect of a unique exercise programme (Fall Arrest Strategy Training, or FAST) on upper body strength, range of motion (ROM), and fall risk in older women. FAST was designed to improve upper body capacity to prevent injury when a fall cannot be avoided. Method: A quasi-randomized site design included 71 older women (aged 67-95 y, mean age 83 years), who participated either in a standard fall prevention programme (Staying on Your Feet, or SOYF; n=29) or in SOYF combined with FAST (n=42). The women were measured three times-at baseline, after the 12-week intervention, and again 12 weeks later-for upper body strength, ROM, and fall risk factors (fall risk questionnaire, balance, mobility, and leg strength). Results: No significant differences were found in age, physical activity, or cognitive or functional status between the SOYF-standard and the SOYF-FAST groups. Both groups improved their fall risk status after the intervention, with no significant differences between them; however, the SOYF-FAST group showed greater improvements in upper extremity strength and ROM (p=0.007). Conclusion: FAST can feasibly be integrated into fall prevention programming, with additional gains in upper body strength and ROM in older women.

Objectif : déterminer l'effet d'un programme d'exercices unique (Fall Arrest Strategy Training, ou formation sur la stratégie d'arrêt des chutes, FAST) sur la force du haut du corps, l'amplitude de mouvements (AdM) et le risque de chute chez les femmes âgées. Le programme FAST vise à améliorer la capacité du haut du corps à prévenir les blessures lorsqu'il est impossible d'éviter une chute. Méthodologie : l'étude quasi aléatoire dans le milieu incluait 71 femmes âgées (de 67 à 95 ans, âge moyen de 83 ans), qui ont participé soit à un programme de prévention des chutes standard (Staying on Your Feet, ou rester sur ses pieds, SOYF), soit aux programmes SOYF et FAST combinés (n=29 et n=42, respectivement). Les femmes ont été mesurées trois fois (au début, après l'intervention de 12 semaines, puis de nouveau 12 semaines plus tard), afin d'évaluer la force du haut de leur corps, leur AdM et les facteurs de risque de chute (questionnaire sur le risque de chute, équilibre, mobilité et force des jambes). Résultats : il n'y avait pas de différence significative en matière d'âge, d'activité physique ou d'état cognitif ou fonctionnel entre le groupe SOYF standard et le groupe SOYF­FAST. Les deux groupes avaient réduit leur risque de chute après l'intervention, sans différence significative entre les deux. Cependant, le groupe SOYF­FAST avait amélioré davantage la force du haut du corps et l'AdM (p=0,007). Conclusion : le programme FAST peut être intégré à un programme de prévention des chutes et être également bénéfique pour la force du haut du corps et l'AdM chez les femmes âgées.

Cross-education for improving strength and mobility after distal radius fractures: a randomized controlled trial.

OBJECTIVE: To evaluate the effects of cross-education (contralateral effect of unilateral strength training) during recovery from unilateral distal radius fractures on muscle strength, range of motion (ROM), and function. DESIGN: Randomized controlled trial (26-wk follow-up). SETTING: Hospital, orthopedic fracture clinic. PARTICIPANTS: Women older than 50 years with a unilateral distal radius fracture. Fifty-one participants were randomized and 39 participants were included in the final data analysis. INTERVENTIONS: Participants were randomized to standard rehabilitation (Control) or standard rehabilitation plus strength training (Train). Standard rehabilitation included forearm casting for 40.4±6.2 days and hand exercises for the fractured extremity. Nonfractured hand strength training for the training group began immediately postfracture and was conducted at home 3 times/week for 26 weeks. MAIN OUTCOME MEASURES: The primary outcome measure was peak force (handgrip dynamometer). Secondary outcomes were ROM (flexion/extension; supination/pronation) via goniometer and the Patient Rated Wrist Evaluation questionnaire score for the fractured arm. RESULTS: For the fractured hand, the training group (17.3±7.4kg) was significantly stronger than the control group (11.8±5.8kg) at 12 weeks postfracture (P<.017). There were no significant strength differences between the training and control groups at 9 (12.5±8.2kg; 11.3±6.9kg) or 26 weeks (23.0±7.6kg; 19.6±5.5kg) postfracture, respectively. Fractured hand ROM showed that the training group had significantly improved wrist flexion/extension (100.5°±19.2°) than the control group (80.2°±18.7°) at 12 weeks postfracture (P<.017). There were no significant differences between the training and control groups for flexion/extension ROM at 9 (78.0°±20.7°; 81.7°±25.7°) or 26 weeks (104.4°±15.5°; 106.0°±26.5°) or supination/pronation ROM at 9 (153.9°±23.9°; 151.8°±33.0°), 12 (170.9°±9.3°; 156.7°±20.8°) or 26 weeks (169.4°±11.9°; 162.8°±18.1°), respectively. There were no significant differences in Patient Rated Wrist Evaluation questionnaire scores between the training and control groups at 9 (54.2±39.0; 65.2±28.9), 12 (36.4±37.2; 46.2±35.3), or 26 weeks (23.6±25.6; 19.4±16.5), respectively. CONCLUSIONS: Strength training for the nonfractured limb after a distal radius fracture was associated with improved strength and ROM in the fractured limb at 12 weeks postfracture. These results have important implications for rehabilitation strategies after unilateral injuries.

Former premenarcheal gymnasts exhibit site-specific skeletal benefits in adulthood after long-term retirement.

Young female gymnasts have greater bone strength compared to controls; although possibly due to selection into gymnastics, it is thought that their loading activity during growth increases their bone mass, influencing both bone geometry and architecture. If such bone mass and geometric adaptations are maintained, this may potentially decrease the risk of osteoporosis and risk of fracture later in life. However, there is limited evidence of the persisting benefit of gymnastic exercise during growth on adult bone geometric parameters. Therefore, the purpose of this study was to determine whether adult bone geometry, volumetric density, and estimated strength were greater in retired gymnasts compared to controls, 10 years after retirement from the sport. Bone geometric and densitometric parameters, measured by peripheral quantitative computed tomography (pQCT) at the radius and tibia, were compared between 25 retired female gymnasts and 22 controls, age range 22 to 30 years, by multivariate analysis of covariance (covariates: age, height, and muscle cross-sectional area). Retired gymnasts had significantly greater adjusted total and trabecular area (16%), total and trabecular bone mineral content (BMC) (18% and 22%, respectively), and estimated strength (21%) at the distal radius (p < 0.05) than controls. Adjusted total and cortical area and BMC, medullary area, and estimated strength were also significantly greater (13% to 46%) in retired gymnasts at the 30% and 65% radial shaft sites (p < 0.05). At the distal tibia, retired gymnasts had 12% to 13% greater total and trabecular BMC and volumetric bone mineral density as well as 21% greater estimated strength; total and cortical BMC and estimated strength were also greater at the tibial shaft (8%, 11%, and 10%, respectively) (p < 0.05). Former female gymnasts have significantly better geometric and densitometric properties, as well as estimated strength, at the radius and tibia 10 years after retirement from gymnastics compared to females who did not participate in gymnastics in childhood and adolescence.

Risk factors for falls in older adults with lower extremity arthritis: a conceptual framework of current knowledge and future directions.

PURPOSE: As the numbers of Canadians aged 65 years and over increases over the next 20 years, the prevalence of chronic conditions, including arthritis, will rise as will the number of falls. Although known fall-risk factors are associated with hip and knee osteoarthritis (OA), minimal research has evaluated fall and fracture risk and/or rates in this population. Thus, the purpose was to summarize research on fall and fracture risk in older adults with hip or knee OA and to develop a conceptual framework of fall-risk screening and assessment. METHOD: The International Classification of Functioning, Disability and Health, clinical practice guidelines for fall-risk screening, and a selected literature review were used. RESULTS: Gaps exist in our knowledge of fall and fracture risk for this population. Muscle performance, balance, and mobility impairments have been identified, but little is known about whether personal and environmental contextual factors impact fall and fracture risk. Physical activity may help to prevent falls, but non-adherence is a problem. CONCLUSION: A need exists to assess fall risk in older adults with hip and knee OA. Promoting regular physical activity by focusing on disease- and activity-specific personal contextual factors may help direct treatment planning.

Objectif : Le nombre de Canadiens de 65 ans et plus augmentera au cours des 20 prochaines années et la prévalence des maladies chroniques, dont l'arthrite, sera en hausse, tout comme le nombre de chutes. Bien que des facteurs de risques de chute connus soient associés à l'arthrose du genou ou de la hanche, une somme minimale de recherches a évalué les risques ou les taux de chutes et de fractures chez ce segment de la population. En conséquence, l'objectif de cette étude était de dresser un résumé des recherches réalisées sur les risques de chute ou de fracture chez les adultes plus âgés aux prises avec de l'arthrose au genou ou à la hanche, et d'élaborer un cadre conceptuel pour le dépistage et l'évaluation des risques de chute. Méthode : La Classification internationale du fonctionnement, du handicap et de la santé (CIF), qui forme les directives cliniques pour le dépistage des risques de chute, et une revue documentaire sélective ont été utilisées. Résultats : Il existe des lacunes dans nos connaissances relatives aux risques de chute et de fracture au sein de ce segment de la population. La dégradation de la performance musculaire, de l'équilibre et de la mobilité a été établie, mais on sait peu de choses en ce qui a trait aux répercussions possibles de facteurs contextuels personnels ou environnementaux sur les risques de chute ou de fracture. L'activité physique peut aider à prévenir les chutes, mais la non-adhésion des patients à un programme d'activité physique pose problème. Conclusion : Une évaluation des risques de chute chez les adultes plus âgés souffrant d'arthrose du genou ou de la hanche est nécessaire. La promotion de l'activité physique régulière, en se concentrant sur les facteurs contextuels personnels propres à la maladie ou à l'activité, pourrait aider directement la planification du traitement.

Higher premenarcheal bone mass in elite gymnasts is maintained into young adulthood after long-term retirement from sport: a 14-year follow-up.

Sports that impact-load the skeleton during childhood and adolescence increase determinants of bone strength such as bone mineral content and density; however, it is unclear if this benefit is maintained after retirement from the sport. The purpose of this study was to assess whether the previously reported higher bone mass in a group of premenarcheal gymnasts was still apparent 10 years after the cessation of participation and withdrawal of the gymnastics loading stimulus. In 1995, 30 gymnasts 8 to 15 years of age were measured and compared with 30 age-matched nongymnasts. Twenty-five former gymnasts and 22 nongymnasts were measured again 14 years later (2009 to 2010). Gymnasts had been retired from gymnastics training and competition for an average of 10 years. Total body (TB), lumbar spine (LS), and femoral neck (FN) bone mineral content (BMC) was assessed at both measurement occasions by dual-energy X-ray absorptiometry (DXA). Multivariate analysis of covariance (MANCOVA) was used to compare former gymnasts' and nongymnasts' BMC while controlling for differences in body size and maturation (covariates: age, height, weight, and years from menarche [1995] or age at menarche [2009 to 2010]). Premenarcheal gymnasts (measured in 1995) had significantly greater size-adjusted TB, LS, and FN BMC (p < 0.05) (15%, 17%, and 12%, respectively) than nongymnasts. Ten years after retirement, gymnasts had maintained similar size-adjusted TB, LS, and FN BMC differences (p < 0.05) (13%, 19%, and 13%, respectively) when compared with nongymnasts. Bone mass benefits in premenarcheal gymnasts were still apparent even after long-term (10 years) removal of the gymnastics loading stimulus.

The effect of aquatic exercise and education on lowering fall risk in older adults with hip osteoarthritis.

OBJECTIVE: To evaluate the effect of aquatic exercise and education on fall risk factors in older adults with hip osteoarthritis (OA). METHOD: Seventy-nine adults, 65 years of age or older with hip OA and at least 1 fall risk factor, were randomly assigned to 1 of 3 groups: aquatics and education (AE; aquatic exercise twice a wk with once-a-wk group education), aquatics only (A; 2 wk aquatic exercise) and control (C; usual activity). Balance, falls efficacy, dual-task function, functional performance (chair stands), and walking performance were measured pre- and postintervention or control period. RESULTS: There was a significant improvement in fall risk factors (full-factorial MANCOVA, baseline values as covariates; p = .038); AE improved in falls efficacy compared with C and in functional performance compared with A and C. CONCLUSION: The combination of aquatic exercise and education was effective in improving fall risk factors in older adults with arthritis.

The reliability and validity of handheld dynamometry for the measurement of lower-extremity muscle strength in older adults.

Lower-extremity muscle strength is important in predicting fall risk in older adults. Handheld dynamometry (HHD) is a tool used to measure isometric muscle strength in the older adult, but few studies have evaluated the utility of HHD for muscle groups beyond knee extension. The purpose of this study was to evaluate the reliability of HHD at the hip, knee, and ankle and to compare HHD strength values to other isometric dynamometry (ID) and to balance and recovery in older adults. This was a repeated measures study design of 18 men and women, age 65 to 92 years of age, who had HHD strength testing 3 to 7 days apart by the same examiner and repeat testing on the same day using 2 independent examiners. ID strength, balance, step length, and reaction time were measured once. HHD demonstrated good intrarater and interrater reliability for isometric strength at the hip and knee but was not a reliable measure for ankle strength. The HHD was a valid measure of isometric strength at the hip and knee, demonstrating moderate to high correlation values when compared to ID strength measures (r = 0.57-0.86; p < 0.05). Hip and knee strength was positively associated to step length and reaction time but not to balance (r = 0.40-0.71; p < 0.05). In conclusion, HHD is a reliable and valid assessment tool for measuring strength at the hip and knee in older adults, and greater strength in these muscles is associated with longer step length and decreased reaction time, which are important components of balance recovery in older adults. HHD can be used as an effective strength measurement tool for the older adult population.

The relationship of intrinsic fall risk factors to a recent history of falling in older women with osteoporosis.

STUDY DESIGN: Cross-sectional descriptive analysis investigating intrinsic fall risk factors in postmenopausal women with osteoporosis. OBJECTIVE: To examine the relationships between history of recent falls and balance, pain, quality of life, function, posture, strength, and mobility. BACKGROUND: Women with osteoporosis who fall are at a high risk of fracture due to decreased bone strength. Identifying fall risk factors for older women with osteoporosis is a crucial step in decreasing the incidence of falls and fracture. METHOD AND MEASURES: Seventy-three women over 60 years of age with established osteoporosis participated in comprehensive testing of fall history, physical function, and quality of life. RESULTS: Significant correlations were found between a recent history of falls and degree of kyphosis (r = 0.29), fear of falls/emotional status (r = -0.27), and balance (r = -0.27). Degree of kyphosis and fear of falls/emotional status explained 20% of the variance of recent fall history using binary logistic regression. Women with an increased kyphosis were more likely to have had a recent fall (odds ratio [OR], 1.17; 95% CI, 1.03-1.34) and those with better emotional status and less fear of falling were less likely to have had a recent fall (OR, 0.61; 95% CI, 0.38-0.97). CONCLUSION: Increased thoracic kyphosis and fear of falling are 2 intrinsic factors associated with recent falls in women with osteoporosis. To design more effective interventions to decrease fall risk in this population, future prospective, longitudinal studies should monitor kyphosis, fear of falling, balance reactions, and other potential risk factors not identified in this study.