The current study investigated the effect of 2 different types of unilateral resistance training on the postural tremor output of 19 neurologically healthy men age 70–80 yr. The strength- (n = 7) and coordination-training (n = 7) groups trained twice a week for 6 wk, performing dumbbell biceps curls, wrist flexions, and wrist extensions, while the control group (n = 5) maintained their normal activities. Changes in index-finger tremor (RMS amplitude, peak, and proportional power) and upper limb muscle coactivation were assessed during 4 postural conditions that were performed separately with the trained and untrained limbs. The 2 training groups experienced significantly greater reductions in mean RMS tremor amplitude, peak, and proportional tremor power 8–12 Hz and upper limb muscle coactivation, as well as greater increases in strength, than the control group. These results further demonstrate the benefits of resistance training for improving function in older adults.
Justin W.L. Keogh, Steve Morrison and Rod Barrett
Natasha Reid, Justin W. Keogh, Paul Swinton, Paul A. Gardiner and Timothy R. Henwood
This study investigated the association of sitting time with sarcopenia and physical performance in residential aged care residents at baseline and 18-month follow-up. Measures included the International Physical Activity Questionnaire (sitting time), European Working Group definition of sarcopenia, and the short physical performance battery (physical performance). Logistic regression and linear regression analyses were used to investigate associations. For each hour of sitting, the unadjusted odds ratio of sarcopenia was 1.16 (95% confidence interval [0.98, 1.37]). Linear regression showed that each hour of sitting was significantly associated with a 0.2-unit lower score for performance. Associations of baseline sitting with follow-up sarcopenia status and performance were nonsignificant. Cross-sectionally, increased sitting time in residential aged care may be detrimentally associated with sarcopenia and physical performance. Based on current reablement models of care, future studies should investigate if reducing sedentary time improves performance among adults in end of life care.
Hayden J. Pritchard, Matthew J. Barnes, Robin J. Stewart, Justin W. Keogh and Michael R. McGuigan
Purpose: To investigate the effects of strength-training tapers of different intensities but equal volume reductions on neuromuscular performance. Methods: Eleven strength-trained men (21.3 [3.3] y, 92.3 [17.6] kg, relative 1-repetition-maximum deadlift 1.9 [0.2] times bodyweight) completed a crossover study. Specifically, two 4-wk strength-training blocks were followed by a taper week with reduced volume (∼70%) involving either increased (5.9%) or decreased (−8.5%) intensity. Testing occurred pretraining (T1), posttraining (T2), and posttaper (T3). Salivary testosterone and cortisol, plasma creatine kinase, a Daily Analysis of Life Demands in Athletes questionnaire, countermovement jump (CMJ), isometric midthigh pull, and isometric bench press were measured. Results: CMJ height improved significantly over time (P < .001), with significant increases from T1 (38.0 [5.5] cm) to both T2 (39.3 [5.3] cm; P = .010) and T3 (40.0 [5.3] cm; P = .001) and from T2 to T3 (P = .002). CMJ flight time:contraction time increased significantly over time (P = .004), with significant increases from T1 (0.747 [0.162]) to T2 (0.791 [0.163]; P = .012). Isometric midthigh-pull relative peak force improved significantly over time (P = .033), with significant increases from T1 (34.7 [5.0] N/kg) to T2 (35.9 [4.8] N/kg; P = .013). No significant changes were found between tapers. However, the higher-intensity taper produced small effect-size increases at T3 vs T1 for isometric midthigh-pull relative peak force, CMJ height, and flight time:contraction time, while the lower-intensity taper only produced small effect-size improvements at T3 vs T1 for CMJ height. Conclusions: A strength-training taper with volume reductions had a positive effect on power, with a tendency for the higher-intensity taper to produce more favorable changes in strength and power.
Christos K. Argus, Nicholas D. Gill, Justin W.L. Keogh, Michael R. McGuigan and Will G. Hopkins
There is little literature comparing contrast training programs typically performed by team-sport athletes within a competitive phase. We compared the effects of two contrast training programs on a range of measures in high-level rugby union players during the competition season.
The programs consisted of a higher volume-load (strength-power) or lower volume-load (speed-power) resistance training; each included a tapering of loading (higher force early in the week, higher velocity later in the week) and was performed twice a week for 4 wk. Eighteen players were assessed for peak power during a bodyweight countermovement jump (BWCMJ), bodyweight squat jump (BWSJ), 50 kg countermovement jump (50CMJ), 50 kg squat jump (50SJ), broad jump (BJ), and reactive strength index (RSI; jump height divided by contact time during a depth jump). Players were then randomized to either training group and were reassessed following the intervention. Inferences were based on uncertainty in outcomes relative to thresholds for standardized changes.
There were small between-group differences in favor of strength-power training for mean changes in the 50CMJ (8%; 90% confidence limits, ±8%), 50SJ (8%; ±10%), and BJ (2%; ±3%). Differences between groups for BWCMJ, BWSJ, and reactive strength index were unclear. For most measures there were smaller individual differences in changes with strength-power training.
Our findings suggest that high-level rugby union athletes should be exposed to higher volume-load contrast training which includes one heavy lifting session each week for larger and more uniform adaptation to occur in explosive power throughout a competitive phase of the season.
Justin W.L. Keogh, Nicola Power, Leslie Wooller, Patricia Lucas and Chris Whatman
This mixed-methods, quasi-experimental pilot study examined whether the Nintendo Wii Sports (NWS) active video game (exergame) system could significantly improve the functional ability, physical activity levels, and quality of life of 34 older adults (4 men and 30 women, 83 ± 8 yr) living in 2 residential aged-care (RAC) centers. Change score analyses indicated the intervention group had significantly greater increases in bicep curl muscular endurance, physical activity levels, and psychological quality of life than the control group (p < .05). Analysis of the quotes underlying the 3 themes (feeling silly, feeling good; having fun; and something to look forward to) suggested that intervention group participants developed a sense of empowerment and achievement after some initial reluctance and anxiousness. They felt that the games were fun and provided an avenue for greater socialization. These results add some further support to the utilization of NWS exergames in the RAC context.
Asmita Patel, Grant M. Schofield, Gregory S. Kolt and Justin W.L. Keogh
This study examined whether perceived barriers, benefits, and motives for physical activity differed based on allocation to 2 different types of primary-care activity-prescription programs (pedometer-based vs. time-based Green Prescription). Eighty participants from the Healthy Steps study completed a questionnaire that assessed their perceived barriers, benefits, and motives for physical activity. Factor analysis was carried out to identify common themes of barriers, benefits, and motives for physical activity. Factor scores were then used to explore between-groups differences for perceived barriers, benefits, and motives based on group allocation and demographic variables. No significant differences were found in factor scores based on allocation. Demographic variables relating to the existence of chronic health conditions, weight status, and older age were found to significantly influence perceived barriers, benefits, and motives for physical activity. Findings suggest that the addition of a pedometer to the standard Green Prescription does not appear to increase perceived motives or benefits or decrease perceived barriers for physical activity in low-active older adults.
Justin W.L. Keogh, Andrew Kilding, Philippa Pidgeon, Linda Ashley and Dawn Gillis
Dancing is a mode of physical activity that may allow older adults to improve their physical function, health, and well-being. However, no reviews on the physical benefits of dancing for healthy older adults have been published in the scientific literature. Using relevant databases and keywords, 15 training and 3 cross-sectional studies that met the inclusion criteria were reviewed. Grade B–level evidence indicated that older adults can significantly improve their aerobic power, lower body muscle endurance, strength and flexibility, balance, agility, and gait through dancing. Grade C evidence suggested that dancing might improve older adults’ lower body bone-mineral content and muscle power, as well as reduce the prevalence of falls and cardiovascular health risks. Further research is, however, needed to determine the efficacy of different forms of dance, the relative effectiveness of these forms of dance compared with other exercise modes, and how best to engage older adults in dance participation.
Samara Boisen, Chris Krägeloh, Daniel Shepherd, Clare Ryan, Jonathan Masters, Sue Osborne, Rod D. MacLeod, Marion Gray and Justin W. Keogh
Men with prostate cancer experience many side effects and symptoms that may be improved by a physically active lifestyle. It was hypothesized that older men with prostate cancer who were physically active would report significantly higher levels of quality of life (QOL) as assessed by the WHOQOL-BREF and the WHOQOL-OLD. Of the 348 prostate cancer survivors who were invited to participate in the present postal survey, 137 men returned the questionnaires. Those who were physically active had significantly lower prostate specific antigen (PSA) scores and higher social participation than those insufficiently active. These findings offer some support for the benefits of physical activity (PA) within the prostate cancer population in managing the adverse side effects of their treatments on aspects of their QOL. Future research should more closely examine what types of PA best promote improvements in varying aspects of QOL and psychological well-being for prostate cancer survivors.