TT. While extensively examined in able-bodied cycling, 22 , 23 few studies have investigated the impact of anaerobic threshold, anaerobic capacity, and upper-body strength upon handcycling performance. The attainment of high-power output during an all-out sprint is frequently used as a measure of
Jonpaul Nevin and Paul M. Smith
Kieran P. Young, G. Gregory Haff, Robert U. Newton, Tim J. Gabbett, and Jeremy M. Sheppard
To evaluate whether the dynamic strength index (DSI: ballistic peak force/isometric peak force) could be effectively used to guide specific training interventions and detect training-induced changes in maximal and ballistic strength.
Twenty-four elite male athletes were assessed in the isometric bench press and a 45% 1-repetition-maximum (1RM) ballistic bench throw using a force plate and linear position transducer. The DSI was calculated using the peak force values obtained during the ballistic bench throw and isometric bench press. Athletes were then allocated into 2 groups as matched pairs based on their DSI and strength in the 1RM bench press. Over the 5 wk of training, athletes performed either high-load (80–100% 1RM) bench press or moderate-load (40–55% 1RM) ballistic bench throws.
The DSI was sensitive to disparate training methods, with the bench-press group increasing isometric bench-press peak force (P = .035, 91% likely), and the ballistic-bench-throw group increasing bench-throw peak force to a greater extent (P ≤ .001, 83% likely). A significant increase (P ≤ .001, 93% likely) in the DSI was observed for both groups.
The DSI can be used to guide specific training interventions and can detect training-induced changes in isometric bench-press and ballistic bench-throw peak force over periods as short as 5 wk.
Mark R. McKean and Brendan J. Burkett
Dry-land strength training is a fundamental component for elite kayak performance. The aims of this research were 3-fold: 1st, to determine the relationship between performance time and strength scores for elite kayakers; 2nd, to identify how strength changes (gains or losses) over 3 training y relate with changes in performance time for elite kayakers; and 3rd, to compare the progression in performance times for elite athletes with the top 3 performers from the national championships. The performance data for 15 elite male and 10 elite female kayakers were collected over 2 y. This group was reduced to 9 men and 8 women in the 3rd and final year. There were direct and significant correlations between strength scores and performance times across the 3 y. Bench-press 1RM increased by 34.8% for men and 42.3% for women. Over the 3 seasons, mean 1000-m time decreased by approximately 4.8%, 500-m times decreased by 7.3% (women), and 200-m times decreased by 9.1%. The women’s 500-m changed from 11.9% difference from medalists to within 1.1% during the 3 y. During the 3 y of this study a change in 1-repetitionmaximum (1RM) bench press of 13% for men and 6.5% in women coincided with a change in performance times of 1%. For 1RM pull-up a change of 10% in men and 2.3% in women coincided with a change in performance times of 1%.
Cynthia Dawson, Ron Croce, Tim Quinn, and Neil Vroman
Hand-held dynamometry has proven reliable in assessing adult strength. The primary purpose of this study was to determine its reliability in children. Secondary purposes included investigating strength differences between males and females and between dominant (D) and nondominant (ND) sides. Subjects were 8-, 9-, and 10-year-old boys (n=63) and girls (n=54). The Nicholas Manual Muscle Tester (NMMT) was used to measure maximum isometric force of D and ND elbow flexors, elbow extensors, and shoulder abductors. Retest measurements were taken 4 to 7 days later. Results indicated that (a) correlation coefficients ranging from .72 to .90 were statistically significant; (b) except for males’ ND elbow extensor strength, a series of paired t tests revealed no significant differences between test and retest strength values; (c) a series of paired t tests revealed no significant strength differences between D and ND sides other than for males’ elbow extensor strength for the test phase; and (d) a series of unpaired t tests revealed statistically significant differences between males and females on a majority of the muscle groups. The NMMT appears to be a quick and reliable testing instrument for determining maximal isometric force in children.
Kieran P. Young, G. Gregory Haff, Robert U. Newton, and Jeremy M. Sheppard
The purpose of this study was to evaluate the reliability of an isometric-bench-press (IBP) test performed across 4 elbow angles and a ballistic bench throw (BBT) using a relative load, as well as evaluating the reliability of the dynamic strength index (DSI: BBT peak force/IBP peak force).
Twenty-four elite male athletes performed the IBP and a 45% 1-repetition-maximum BBT on 2 separate days with 48 h between testing occasions. Peak force, peak power, peak velocity, peak displacement, and peak rate of force development (PRFD) were assessed using a force plate and linear position transducer. Reliability was assessed by intraclass correlation (ICC), coefficient of variation (%CV) and typical error.
Performance measures in the BBT, such as peak force, peak velocity, peak power, and peak displacement, were considered reliable (ICC = .85–.92, %CV = 1.7–3.3), while PRFD was not (ICC = .43, %CV = 4.1). Similarly, for the IBP, peak force across all angles was considered reliable (ICC = .89–.97, %CV = 1.2–1.6), while PRFD was not (ICC = .56–.65, %CV = 0.5–7.6). The DSI was also reliable (ICC = .93, %CV = 3.5).
Performance measures such as peak force in the IBP and BBT are reliable when assessing upper-body pressing-strength qualities in elite male athletes. Furthermore, the DSI is reliable and could potentially be used to detect qualities of relative deficiency and guide specific training interventions.
Sharon D. Rogers and Shannon E. Jarrott
The purpose of this investigation was to examine the association between cognitive ability and upper body muscle strength. Two sources of existing data were pooled for this examination. Thirty-eight older participants diagnosed with Alzheimer’s disease or dementia (25 women, 13 men; age = 83.2 ± 5.6 years, MMSE score = 16.75 ± 7.04, M ± SD) underwent an assessment of grip strength via handheld dynamometry. Multiple-regression analysis indicated that cognitive status was a significant predictor of strength and, when combined in a model with age and sex, explained 57% of the between-individuals variance in handgrip strength. The findings from this exploratory investigation suggest that dementia is associated with strength loss, a key contributor to functional disability; this further justifies efforts to investigate mechanisms responsible for this decay and to preserve muscle integrity by integrating physical activity interventions, notably, muscle strengthening, into the lifestyle of adults with dementia.
Johann C. Bilsborough, Kate Greenway, Steuart Livingston, Justin Cordy, and Aaron J. Coutts
The purpose of this study was to examine the seasonal changes in body composition, nutrition, and upper-body (UB) strength in professional Australian Football (AF) players. The prospective longitudinal study examined changes in anthropometry (body mass, fat-free soft-tissue mass [FFSTM], and fat mass) via dual-energy X-ray absorptiometry 5 times during an AF season (start preseason, midpreseason, start season, midseason, end season) in 45 professional AF players. Dietary intakes and strength (bench press and bench pull) were also assessed at these time points. Players were categorized as experienced (>4 y experience, n = 23) or inexperienced (<4 y experience, n = 22). Fat mass decreased during the preseason but was stable through the in-season for both groups. %FFSTM was increased during the preseason and remained constant thereafter. UB strength increased during the preseason and was maintained during the in-season. Changes in UB FFSTM were related to changes in UB-strength performance (r = .37−.40). Total energy and carbohydrate intakes were similar between the experienced and inexperienced players during the season, but there was a greater ratio of dietary fat intake at the start-preseason point and an increased alcohol, reduced protein, and increased total energy intake at the end of the season. The inexperienced players consumed more fat at the start of season and less total protein during the season than the experienced players. Coaches should also be aware that it can take >1 y to develop the appropriate levels of FFSTM in young players and take a long-term view when developing the physical and performance abilities of inexperienced players.
Katie J. Thralls and Susan S. Levy
for the duration of the test as they complete as many full repetitions in the time allotted. Incomplete repetitions, excessive rocking, or removal of hands from the shoulders are not counted. Lower body strength is needed for getting in and out of bed, chairs, and toileting. Upper body strength: This
Konstantinos D. Tambalis, Stamatis Mourtakos, and Labros S. Sidossis
maternal nutrition, paternal BMI, sexual maturity, and fat-free mass and the PA status of children, were not included in the analysis. Conclusion We found small but inverse associations between mppBMI and GWG and all PF components (lower and upper body strength, CRF, and speed) among 8- to 9-year
Jozo Grgic, Filip Sabol, Sandro Venier, Ivan Mikulic, Nenad Bratkovic, Brad J. Schoenfeld, Craig Pickering, David J. Bishop, Zeljko Pedisic, and Pavle Mikulic
·kg −1 ( d = 0.09; +2.1 kg; P = .007) of caffeine acutely enhanced upper-body strength. In comparisons with no placebo control condition, no significant differences were observed for 2 mg·kg −1 ( d = 0.01; +0.2 kg; P = .656). In comparisons with placebo control condition, post hoc tests revealed