scholarly journals Using Bilateral Functional and Anthropometric Tests to Define Symmetry in Cross-Country Skiers

2017 ◽  
Vol 60 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Glenn Björklund ◽  
Marie Alricsson ◽  
Ulla Svantesson

AbstractThe aim of this study was to evaluate the symmetry of anthropometry and muscle function in cross-country skiers and their association to vertical jumping power. Twenty cross-country skiers were recruited (21.7 ± 3.8 yrs, 180.6 ± 7.6 cm, 73.2 ± 7.6 kg). Anthropometric data was obtained using an iDXA scan. VO2maxwas determined using the diagonal stride technique on a ski treadmill. Bilateral functional tests for the upper and lower body were the handgrip and standing heel-rise tests. Vertical jump height and power were assessed with a counter movement jump. Percent asymmetry was calculated using a symmetry index and four absolute symmetry index levels. At a group level the upper body was more asymmetrical with regard to lean muscle mass (p = 0.022, d = 0.17) and functional strength (p = 0.019, d = 0.51) than the lower body. At an individual level the expected frequencies for absolute symmetry level indexes showed the largest deviation from zero for the heel-rise test (χ2 = 16.97, p = 0.001), while the leg lean mass deviated the least (χ2 = 0.42, p = 0.517). No relationships were observed between absolute symmetry level indexes of the lower body and counter movement jump performance (p > 0.05). As a group the skiers display a more asymmetrical upper body than lower body regarding muscle mass and strength. Interestingly at the individual level, despite symmetrical lean leg muscle mass the heel-rise test showed the largest asymmetry. This finding indicates a mismatch in muscle function for the lower body.

2019 ◽  
Vol 4 (2) ◽  
pp. 18 ◽  
Author(s):  
Michael Timothy Lane ◽  
Mark Travis Byrd ◽  
Zachary Bell ◽  
Tyler Hurley

Currently there is a lack of research into how women respond to pre-workout supplementation. The effects of supplements on exercise performance in women, specifically to power, must be performed. This study investigated the effects of supplementation on power production and maintenance during a high-intensity cycle ergometry sprint performance, vertical jump performance, and bench press performance in women. It also investigated the effects of supplementation on power production and the maintenance of upper and lower body tasks in women. A total of 23 females (22.9 ± 3.6 years, 175.6 ± 6.5 cm, 86.9 ± 15.1 kg, 19.1 ± 8.4 body fat percentage (BF%) (mean ± std. dev.)) were familiarized with the testing protocol and maximal bench press performances were attained (49.5 ± 15.4kg). Utilizing a double-blind crossover design, subjects completed three trials of: Five countermovement vertical jumps, a high-intensity cycle sprint protocol, which consisted of 10 maximal, five second cycle ergometer sprints. Subjects performed a velocity bench press test, utilizing 80% of their predetermined one repetition maximum (1RM) for 10 sets of three repetitions for maximal speed. For 20 min prior to each trial, the subjects ingested, in a randomized order, a pre-workout supplement (Supp), placebo+150 mg caffeine (Caff), or a placebo (PL). Peak power (PP), mean power (MP), and minimum power (MNP) were recorded for each sprint. Maximal velocity from each set was also recorded. Bike sprint and bench press data were normalized to the placebo trial for analysis. Blood lactate (bLa−) was measured immediately prior to each testing session, within 2 min of the completion of the last cycle sprint and following the bench press test. Bike sprint and bench press testing showed no significant differences through the testing sessions, but did significantly decline over test battery (p < 0.05). Vertical jump performance and lactate levels were not significantly different. Supplementation with a pre-workout supplement or placebo with caffeine 20 min prior to participation showed no positive benefits to performance in female participants.


2009 ◽  
Vol 21 (1) ◽  
pp. 34-46 ◽  
Author(s):  
James L. Nuzzo ◽  
Michael J. Cavill ◽  
N. Travis Triplett ◽  
Jeffrey M. McBride

The primary purpose of this investigation was to provide a descriptive analysis of lower-body strength and vertical jump performance in overweight male (n = 8) and female (n = 13) adolescents. Maximal strength was tested in the leg press and isometric squat. Kinetic and kinematic variables were assessed in vertical jumps at various loads. When compared with females, males demonstrated significantly greater (p ≤ .05) absolute maximal strength in the leg press. However, when maximal strength was expressed relative to body mass, no significant difference was observed. There were no significant differences between males and females in vertical jump performance at body mass.


2021 ◽  
Vol 3 ◽  
Author(s):  
Linda Marie Hansen ◽  
Øyvind Sandbakk ◽  
Gertjan Ettema ◽  
Julia Kathrin Baumgart

Purpose: To investigate the interaction between exercise modality (i.e., upper- and lower-body exercise) and sex in physiological responses and power output (PO) across the entire intensity spectrum (i.e., from low to maximal intensity).Methods: Ten male and 10 female cross-country (XC) skiers performed a stepwise incremental test to exhaustion consisting of 5 min stages with increasing workload employing upper-body poling (UP) and running (RUN) on two separate days. Mixed measures ANOVA were performed to investigate the interactions between exercise modalities (i.e., UP and RUN) and sex in physiological responses and PO across the entire exercise intensity spectrum.Results: The difference between UP and RUN (ΔUP−RUN), was not different in the female compared with the male XC skiers for peak oxygen uptake (18 ± 6 vs. 18 ± 6 mL·kg−1·min−1, p = 0.843) and peak PO (84 ± 18 vs. 91 ± 22 W, p = 0.207). At most given blood lactate and rating of perceived exertion values, ΔUP−RUN was larger in the male compared with the female skiers for oxygen uptake and PO, but these differences disappeared when the responses were expressed as % of the modality-specific peak.Conclusion: Modality-differences (i.e., ΔUP−RUN) in peak physiological responses and PO did not differ between the female and male XC skiers. This indicates that increased focus on upper-body strength and endurance training in female skiers in recent years may have closed the gap between upper- and lower-body endurance capacity compared with male XC skiers. In addition, no sex-related considerations need to be made when using relative physiological responses for intensity regulation within a specific exercise modality.


2005 ◽  
Vol 37 (Supplement) ◽  
pp. S182???S183
Author(s):  
Hugo Olmedillas ◽  
Jorge Perez-Gomez ◽  
German Vicente-Rodriguez ◽  
Safira Delgado-Guerra ◽  
Ignacio Ara ◽  
...  

2019 ◽  
Vol 54 (10) ◽  
pp. 573-581 ◽  
Author(s):  
Kerry R O’Bryan ◽  
Thomas M Doering ◽  
Robert W Morton ◽  
Vernon G Coffey ◽  
Stuart M Phillips ◽  
...  

ObjectiveTo determine the effects of multi-ingredient protein (MIP) supplements on resistance exercise training (RT)-induced gains in muscle mass and strength compared with protein-only (PRO) or placebo supplementation.Data sourcesSystematic search of MEDLINE, Embase, CINAHL and SPORTDiscus.Eligibility criteriaRandomised controlled trials with interventions including RT ≥6 weeks in duration and a MIP supplement.DesignRandom effects meta-analyses were conducted to determine the effect of supplementation on fat-free mass (FFM), fat mass, one-repetition maximum (1RM) upper body and 1RM lower body muscular strength. Subgroup analyses compared the efficacy of MIP supplementation relative to training status and chronological age.ResultsThe most common MIP supplements included protein with creatine (n=17) or vitamin D (n=10). Data from 35 trials with 1387 participants showed significant (p<0.05) increases in FFM (0.80 kg (95% CI 0.44 to 1.15)), 1RM lower body (4.22 kg (95% CI 0.79 to 7.64)) and 1RM upper body (2.56 kg (95% CI 0.79 to 4.33)) where a supplement was compared with all non-MIP supplemented conditions (means (95% CI)). Subgroup analyses indicated a greater effect of MIP supplements compared with all non-MIP supplements on FFM in untrained (0.95 kg (95% CI 0.51 to 1.39), p<0.0001) and older participants (0.77 kg (95% CI 0.11 to 1.43), p=0.02); taking MIP supplements was also associated with gains in 1RM upper body (1.56 kg (95% CI 0.80 to 2.33), p=0.01) in older adults.Summary/conclusionsWhen MIP supplements were combined with resistance exercise training, there were greater gains in FFM and strength in healthy adults than in counterparts who were supplemented with non-MIP. MIP supplements were not superior when directly compared with PRO supplements. The magnitude of effect of MIP supplements was greater (in absolute values) in untrained and elderly individuals undertaking RT than it was in trained individuals and in younger people.Trial registration numberCRD42017081970.


Author(s):  
Aruna Gulati ◽  
Rita Jain ◽  
Anuradha Lehri ◽  
Rajneesh Kumar

This study aimed to assess the effect of high and low levels of flexibility on key performance indicators of volleyball performance. Eighty-four volleyball players (n=84; mean±SD; decimal age: 16.57±1.51; height (cm): 176.23±8.77; body mass (kg): 66.14±11.79) were selected for the study. The design of the study was cross-sectional and to measure selected variables i.e. agility, lower body muscular power, and acceleration speed; 6×10 m shuttle run, countermovement jump (with arm swing) test and 20 m sprint test (standing start) were used. To measure the flexibility level of the players, sit and reach test was used. Shapiro-Wilk normality test was conducted to check the distribution of data and the Levine test was applied to check homogeneity of the variance in data. Participants were divided into two groups i.e. High Flexibility Group (HFG) and Low Flexibility Group (LFG) using k-means cluster analysis and independent t-test was applied to find the differences between HFG and LFG. The level of significance was set at p < 0.05. Results showed statistically significant difference between HFG and LFG in agility, acceleration speed and lower body muscular power and, based on the results, it was concluded coaches should include flexibility training in the regular training programme. The results obtained supported the rationale that baseline flexibility may influence the performance of volleyball players. <p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/edu_01/0778/a.php" alt="Hit counter" /></p>


Vibration ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 759-767
Author(s):  
Nicole C. Dabbs ◽  
Sergio Espericueta ◽  
Sean Bonilla ◽  
Margaret T. Jones

The purpose of this study is to determine the effects of coupling WBV and acute muscular fatigue to determine its effects on countermovement vertical jump (CMVJ) performance and isometric mid-thigh pull (IMTP). Twenty-eight healthy active adults volunteered for five-day study. Testing sessions 2–5 included one of four conditions: No WBV and no fatigue (CON), WBV and fatigue (WBV + FAT), WBV and no fatigue (WBV), and no WBV and fatigue (FAT). WBV was performed using a frequency of 50 Hz and a low amplitude while performing quarter squats for a total of 4 min with a 30 s rest or work ratio. Lower-body fatigue induced using Bosco fatigue protocol. CMVJ and IMTP were performed on force plates. SPSS was used to perform a 2 × 2 Repeated Measures ANOVA. Significant main effects were found for fatigue in CMVJ-height and CMVJ-peak ground reaction force, no significant main effect for WBV, and no significant interactions. Lower-body fatigue decreases vertical jump performance, and WBV did not attenuate the detrimental effects of lower-body fatigue.


Nutrients ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 3757
Author(s):  
Ellem Eduarda Pinheiro dos Santos ◽  
Rodrigo Cappato de de Araújo ◽  
Darren G. Candow ◽  
Scott C. Forbes ◽  
Jaddy Antunes Guijo ◽  
...  

Sarcopenia refers to the age-related loss of muscle strength and muscle mass, which is associated with a reduced quality of life, particularly in older females. Resistance training (RT) is well established to be an effective intervention to counter indices of sarcopenia. Accumulating research indicates that the addition of creatine supplementation (Cr) to RT augments gains in muscle strength and muscle mass, compared to RT alone. However, some evidence indicates that sex differences may alter the effectiveness of Cr. Therefore, we systematically reviewed randomized controlled trials (RCTs) investigating the efficacy of Cr + RT on measures of upper- and lower-body strength and muscle mass in older females. A systematic literature search was performed in nine electronic databases. Ten RCTs (N = 211 participants) were included the review. Overall, Cr significantly increased measures of upper-body strength (7 studies, n = 142, p = 0.04), with no effect on lower-body strength or measures of muscle mass. Sub-analyses revealed that both upper-body (4 studies, n = 97, p = 0.05) and lower-body strength (4 studies, n = 100, p = 0.03) were increased by Cr, compared to placebo in studies ≥ 24 weeks in duration. In conclusion, older females supplementing with Cr experience significant gains in muscle strength, especially when RT lasts for at least 24 weeks in duration. However, given the level of evidence, future high-quality studies are needed to confirm these findings.


Author(s):  
Catarina N. Matias ◽  
Francesco Campa ◽  
Catarina L. Nunes ◽  
Rubén Francisco ◽  
Filipe Jesus ◽  
...  

Background: An increasing body of evidence indicates that the phase angle (PhA) can be applied as a marker of nutritional status, disease prognosis, and mortality probability. Still, it is not known whether PhA can be used as an indicator of muscular quantity and strength and maximal aerobic capacity in overweight/obese former highly active individuals, an understudied population. This study aimed to analyze the association between PhA with skeletal muscle mass, maximal isometric strength, and maximal aerobic capacity through VO2max, in overweight/obese and inactive former athletes. Methods: Cross-sectional information of 94 (62 males) former adult athletes (age: 43.1 ± 9.4 years old; body mass index: 31.4 ± 4.8 kg/m2) taking part in a weight-loss clinical trial was analyzed. Total fat and fat-free mass were determined by dual-energy X-ray absorptiometry, while skeletal muscle mass was predicted from appendicular lean soft tissue. Values for upper- and lower-body maximal isometric strength were assessed by handgrip and leg press dynamometry. VO2max was determined by indirect calorimetry through a graded exercise test performed on a treadmill. Results: PhA was associated with skeletal muscle mass (r = 0.564, p < 0.001), upper-body strength (r = 0.556, p < 0.001), lower-body strength (r = 0.422, p < 0.001), and VO2max (r = 0.328, p = 0.013). These relationships remained significant for skeletal muscle mass (β = 2.158, p = 0.001), maximal isometric strength (upper-body: β = 2.846, p = 0.012; low-er-body: β = 24.209, p = 0.041) after adjusting for age, sex, and fat mass but not for VO2max (β = −0.163, p = 0.098). Conclusion: Our findings indicated that former athletes with higher values of PhA exhibited greater muscle mass and strength, despite sex, age, and body composition, which suggests that this simple raw BI parameter can be utilized as an indicator of muscle quantity and functionality in overweight/obese former athletes.


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