High and odd impact exercise training improved physical function and fall risk factors in community-dwelling older men

High impact exercise programmes can improve bone strength, but little is known about whether this type of training further benefits fracture risk by improving physical function in older people. Objectives: This study investigated the influence of high impact exercise on balance, muscle function and morphology in older men. Methods: Fifty, healthy men (65-80 years) were assigned to a 6-month multidirectional hopping programme (TG) and twenty age and physical activity matched volunteers served as controls (CG). Before and after training, muscle function (hop performance, leg press and plantar- and dorsiflexion strength) and physiological determinants (muscle thickness and architecture) as well as balance control (sway path, one leg stance duration) were measured. Resting gastrocnemius medialis (GM) muscle thickness and architecture were assessed using ultrasonography. Results: Significant improvements in hop impulse (+12%), isometric leg-press strength (+4%) and ankle plantarflexion strength (+11%), dorsiflexor strength (+20%) were found in the TG compared to the CG (ANOVA interaction, P<0.05) and unilateral stance time improved over time for TG. GM muscle thickness indicated modest hypertrophy (+4%), but muscle architecture was unchanged. Conclusion: The positive changes in strength and balance after high impact and odd impact training would be expected to improve physical function in older adults

Multidirectional hopping exercise improved balance and ankle plantarflexion strength in community-dwelling older men [Abstract]

Multidirectional hopping exercise improved balance and ankle plantarflexion strength in community-dwelling older men [Abstract

High impact exercise increased femoral neck bone mineral density in older men: a randomised unilateral intervention

Introduction: There is little evidence as towhether exercise can increase BMD in oldermenwith no investigation of high impact exercise. Lifestyle changes and individual variability may confound exercise trials but can be minimised using a within-subject unilateral design (exercise leg [EL] vs. control leg [CL]) that has high statistical power. Purpose: This study investigated the influence of a 12 month high impact unilateral exercise intervention on femoral neck BMD in older men. Methods: Fifty, healthy, community-dwelling older men commenced a 12 month high impact unilateral exercise intervention which increased to 50 multidirectional hops, 7 days a week on one randomly allocated leg. BMD of both femurswasmeasured using dual energy X-ray absorptiometry (DXA) before and after 12 months of exercise, by an observer blind to the leg allocation. Repeated measures ANOVAwith post hoc tests was used to detect significant effects of time, leg and interaction. Results: Thirty-five men (mean±SD, age 69.9±4.0 years) exercised for 12 months and intervention adherence was 90.5±9.1% (304±31 sessions completed out of 336 prescribed sessions). Fourteen men did not complete the 12 month exercise intervention due to: health problems or injuries unrelated to the intervention (n=9), time commitments (n=2), or discomfort during exercise (n=3), whilst BMD data were missing for one man. Femoral neck BMD, BMC and cross-sectional area all increased in the EL (+0.7, +0.9 and +1.2 % respectively) compared to the CL (−0.9,−0.4 and −1.2%); interaction effect Pb0.05. Although the interaction term was not significant (P>0.05), there were significantmain effects of time for sectionmodulus (P=0.044) and minimum neck width (P=0.006). Sectionmodulus increased significantly in the EL (P=0.016) but not in the CL (P=0.465); mean change+2.3% and+0.7% respectively, whereasminimumneck width increased significantly in the CL (P=0.004) but not in the EL (P=0.166); mean changes being +0.7% and +0.3% respectively. Conclusion: A 12 month high impact unilateral exercise intervention was feasible and effective for improving femoral neck BMD, BMC and geometry in older men. Carefully targeted high impact exercises may be suitable for incorporation into exercise interventions aimed at preventing fractures in healthy community-dwelling older men

The influence of high impact exercise on cortical and trabecular bone mineral content and 3D distribution across the proximal femur in older men: a randomised controlled unilateral intervention

Regular exercisers have lower fracture risk, despite modest effects of exercise on BMC. Exercise may produce localised cortical and trabecular bone changes that affect bone strength independently of BMC. We previously demonstrated that brief, daily unilateral hopping exercises increased femoral neck BMC in the exercise leg versus the control leg of older men. This study evaluated the effects of these exercises on cortical and trabecular bone and its 3D distribution across the proximal femur, using clinical computed tomography (CT). Fifty healthy men had pelvic CT scans before and after the exercise intervention. We used hip QCT analysis to quantify BMC in traditional regions of interest and estimate biomechanical variables. Cortical bone mapping localised cortical mass surface density and endocortical trabecular density changes across each proximal femur, which involved registration to a canonical proximal femur model. Following statistical parametric mapping, we visualised and quantified statistically significant changes of variables over time in both legs, and significant differences between legs. Thirty-four men aged 70 (4) years exercised for 12-months, attending 92% of prescribed sessions. In traditional ROIs, cortical and trabecular BMC increased over time in both legs. Cortical BMC at the trochanter increased more in the exercise than control leg, whilst femoral neck buckling ratio declined more in the exercise than control leg. Across the entire proximal femur, cortical mass surface density increased significantly with exercise (2.7%; P 6%) at anterior and posterior aspects of the femoral neck and anterior shaft. Endocortical trabecular density also increased (6.4%; P 12% at the anterior femoral neck, trochanter and inferior femoral head. Odd impact exercise increased cortical mass surface density and endocortical trabecular density, at regions that may be important to structural integrity. These exercise-induced changes were localised rather than being evenly distributed across the proximal femur. This article is protected by copyright. All rights reserved

Brief high impact exercise increased cortical mass and trabecular density at regions predictive of femoral neck and trochanteric fracture [Abstract]

Brief high impact exercise increased cortical mass and trabecular density at regions predictive of femoral neck and trochanteric fracture [Abstract

The influence of high impact exercise on musculoskeletal health in older men

There is little evidence as to whether exercise can improve the musculoskeletal health of older men, with no investigation of high impact exercise. This research compared the multiple joint muscle function of young (n=21) and older men (n=23) and then investigated the feasibility and influence of high impact, unilateral exercise on lower-extremity muscle function (in 3- and 6-month intervention trials) and proximal femur strength (in a 12-month intervention trial) in healthy community-dwelling older men (n=112). In study one, young and older men performed isometric (maximum and explosive) and dynamic contractions on a leg press dynamometer instrumented to record force and displacement, from which the force-velocity and power-velocity relationships were assessed. The results demonstrated that force (-20%) and velocity (-11%) were lower in older men, with the decrement in force being the major explanation for the attenuation of power during a functionally relevant multiple joint movement. During study two, in addition to the previous muscle function assessments, hop performance (net impulse) and static unilateral balance were measured before and after a 3-month high impact, unilateral exercise programme (home-based and supervised group sessions) in older men (n=20). The feasibility of this type of exercise in older men was also determined. The intervention appeared safe and feasible with no adverse effects, however there was no effect on muscle function. In study three, the influence of a longer-term (6-months) high impact, unilateral exercise intervention on muscle function was investigated in older men (exercise group n=39, control group n=18). The specific functional measurements included hop performance (net impulse), ankle plantar and dorsiflexion strength, leg press strength and static unilateral balance. Improvements in net hop impulse (12%), isometric leg press strength (4%), ankle plantarflexion strength (11%) and static unilateral balance (45%) were noted following the intervention. In studies four and five, the effect of a 12-month high impact, unilateral exercise programme on bone strength was investigated. Fifty, older men commenced the training which increased to 50 multidirectional hops, 7 days a week on one randomly allocated leg [exercise leg versus control leg]). Dual energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) scans were performed before and after the intervention. The results from study four revealed that femoral neck areal bone mineral density (aBMD) and bone mineral content (BMC) modestly increased in the exercise leg (n=35; +0.7 and +0.9%) compared to the control leg (n=35; -0.9 and -0.4%) following the intervention. In study five, a segmental QCT analysis of the mid-femoral neck was applied to explore regional changes in cortical thickness in response to the high impact training. The findings demonstrated that cortical thickness increased in the super region at the mid-femoral neck (15-52%), thus producing a greater localised thickening of the cortex. The research presented in this thesis provides a comprehensive evaluation of the influence of high impact exercise on musculoskeletal health and suggests that carefully targeted high impact exercises may be suitable for incorporation into exercise interventions aimed at preventing hip fracture in healthy community-dwelling older men

Increases in proximal femur bone strength estimated using finite element models from computed tomography scans following brief, high impact exercise in older men [Abstract]

Increases in proximal femur bone strength estimated using finite element models from computed tomography scans following brief, high impact exercise in older men [Abstract