Association Between Single-Leg Agility and Single-Leg Vertical Jumping Performance in Active Adults

The vertical jump is crucial in sports and indicates lower body explosiveness. Additionally, vertical jumping requires landing bilaterally or unilaterally. PURPOSE: To determine any differences in unilateral vertical jump performance when landing unilaterally or bilaterally. METHODS: Thirty recreationally trained individuals (age = 23.5 ± 2.2 years) performed three trials of vertical jumps under four different conditions in random order (unilateral-left vertical jump with bilateral landing, unilateral-right vertical jump with bilateral landing, unilateral-left vertical jump with ipsilateral landing, and unilateral-right vertical jump with ipsilateral landing). Kinetic data (peak force, relative peak force, peak power, and relative peak power) was obtained from all jumps at 1000 Hz sampling rate. The average score between trials for the vertical jump were used for statistical analysis in SPSS 25. Independent T-tests were used to find differences in vertical jump measures depending on landing condition with p-value at 0.05. RESULTS: No significant differences between limbs in jump height (Right = 0.08 cm ± 0.04; Left cm = 0.11 ± 0.05), peak force (Right = 473.3 N ± 135.6; Left = 600.1 N ± 182.6), relative peak force (Right = 6.8 N*kg ± 2.6; Left = 7.8 N*kg ± 1.9), peak power (Right = 1505.4 W ± 524.5; Left = 1934.9 W ± 771.9), and relative peak power (Right = 21.3 W*kg ± 7.2; Left = 25.5 W*kg ± 5.8) during unilateral vertical jumps between the landing conditions (p \u3e 0.05). CONCLUSION: It appears that landing conditions do not affect unilateral jump performance in recreationally trained athletes

The Relationship between Squat Jump Performance and Sprint Profile in Collegiate Track and Field Athletes

The squat jump (SJ) necessitates the inter-play of various biomechanical components for better jump performance. Good sprint performance requires the inter-play of many of the same biomechanical components. Researchers have previously examined how the speed, force, velocity, and power interact during sprinting, but have yet to examine how these measures are associated with SJ performance measures. PURPOSE: Examine the relationship between squat jump performance measures and the sprint profile measurements of collegiate track and field athletes. METHODS: Twenty-five athletes (18 males and 7 females) completed two squat jump trials with a linear encoder attached to a 45 lbs. bar placed on the athlete’s upper back. Measures of interest during the concentric phase of the SJ included jump height, maximum force, maximum velocity, maximum power, and rate of force development. Athletes then completed two 30-meter acceleration sprints. The MySprint mobile application was used to acquire the athlete’s sprint profile and to assess maximal theoretical horizontal force, maximal theoretical velocity, optimal velocity, maximal theoretical power, maximal speed, maximal ratio of force, force-velocity slope, and decrease in ratio of force. The best trial was used for statistical analysis. Pearson’s or Spearman’s correlation coefficients were conducted between SJ measures and sprint profile measures. RESULTS: There was a positive correlation between SJ height and maximal speed (r = 0.402; p = 0.042). Maximal power during the SJ was positively correlated with maximal speed (r = 0.476; p = 0.014); optimal velocity (r = 0.469; p = 0.018); maximal theoretical power (r = 0.462; p = 0.018); maximal theoretical velocity (r = 0.452; p = 0.021); theoretical horizontal force (r = 0.431; p = 0.028); and maximal ratio force (r = 0.428; p = 0.029). Maximal velocity during the SJ was correlated with maximal speed (r = 0.519; p = 0.007); maximal theoretical velocity (r = 0.499; p = 0.010); optimal velocity (r = 0.486; p = 0.014); and maximal theoretical power (r = 0.484; p = 0.012). No other correlations were significant. CONCLUSION: Maximal velocity and power during the concentric phase of the SJ are moderately to strongly correlated with maximal sprinting speed, velocity, and power. SJ height is positively correlated with maximum sprint speed. There is a lack of significant correlations between other measures of the SJ and sprint profile measures. SJ power and velocity are correlated with sprint performance, therefore power and velocity improved through plyometric SJ training may be transferable to achieve better sprint performance

Scores for the Modified Functional Movement Screen in Active Older Adults

The modified Functional Movement ScreenTM (mFMS), an adapted form of the traditional FMS for older adults, consists of a battery of tests aiming at identifying areas of movement deficiency. Prompt identification of movement deficiency can help exercise practitioners create a tailored program to improve these limitations. PURPOSE: To establish normative values for the mFMS in healthy active older adults. METHODS: There were 141 individuals (56 males and 85 females; mean age ± SD: age 69.51 ± 7.41 years) who participated in the study. Participants performed an 8-10 minute warm-up at a self-selected pace on a treadmill or stationary bike then completed some dynamic stretches. Following the warm-up protocol, the mFMS screening test was administrated, including the deep squat (DS), shoulder mobility screen (SM), lower body motor control screen (LB-MCS), active straight leg raise (ASLR), shoulder and ankle clearing tests. Due to the range of the mFMS scoring criteria (0-3) for screens and (pass/fail) for the clearing tests, all screens (DS, SM, LB-MCS, ASLR) and clearing tests (shoulder and ankle) were analyzed as categorical and not continuous variables. Consequently, percent counts were reported for each variable. RESULTS: The DS, which requires extensive mobility and motor control, presented a challenge for many subjects: only 17.0% of older adults were able to achieve a perfect score during the DS test. The majority of older adults (95%) did not report any pain during the ankle clearing tests. Similarly, a large proportion of older adults did not report any pain during the shoulder clearing tests (95.7% for the right and 96.3% for the left). More than half of the older adult subjects (53.9%) were able to pass both the right and left LB-MCS. A greater percentage of subjects (41.1%) were able to achieve a perfect score on the right SM compared to (26.2%) for the left. Lastly, the majority of subjects completed the ASLR with a perfect score, 68.8% and 68.1% for the right and left legs, respectively. CONCLUSION: This study highlights areas of mobility, stability, and movement proficiency that seem to be of concern across the active older adult population. Mobility among inactive, physically frail or untrained older adults may display lower scores and therefore screening should be approached with caution. Additionally, exercise practitioners working with active older adults may use values reported in this study as a reference point for comparison

Association and predictive abilityof vertical countermovement jump performance on unilateral agility in recreationally trained individuals

© JPES. Introduction: Many sporting activities require both vertical jumping in combination with agility. Yet, both vertical jumping and agility can be executed either bilaterally or unilaterally.Problem Statement and Approach:There exist no literature exploring the association between unilateral agility with vertical jump performance variables.Thus, the purpose of this study was todetermine associationsand predictive ability between performance measures during unilateral and bilateral vertical countermovement jumpswith unilateral agility measures.Material and Method: Thirty recreationally active adults participated in two non-consecutive sessions. During the first session,participants completed three trials of right-sideunilateral countermovement jumps, left-side unilateral countermovement jumps, and bilateral countermovement jumpsin a randomized order. All jumps were performed akimbo, on force platforms, withthirty seconds of rest between trials. During the second session,participantscompleted two distinct unilateral agilitymaneuvers:single leg up three-back one and single leg cross hops, and were given two trials for each maneuver with thirty seconds rest between trials. The average of all completed trials for all countermovement jumps and agility maneuvers were used for statistical analysis. Spearman’sR correlation were used to find significant associations between completion time for the agility maneuvers and jump height, peak force, relative force, peak power, relative peak power, and landing force for all countermovement jumpconditions. Results:There were significant correlations between the cross hop and up three-back one agility maneuver completion time with countermovement jump height, peak force, peak power, relative peak power, and landing force during both unilateral and bilateral jumps. Conclusions:There appears to be an association between certain performance measures during bilateral and unilateral countermovement jumpsand unilateral agility. Peak power and landing force assist in predicting unilateral agility completion time. Therefore, coaches may desire to implement unilateral jumping with individuals necessitating single leg agility to complete their desired exercise or sport activity

The Relationship between Squat Jump Performance and Sprint Profile in Collegiate Track and Field Athletes

The squat jump (SJ) necessitates the inter-play of various biomechanical components for better jump performance. Good sprint performance requires the inter-play of many of the same biomechanical components. Researchers have previously examined how the speed, force, velocity, and power interact during sprinting, but have yet to examine how these measures are associated with SJ performance measures. PURPOSE: Examine the relationship between squat jump performance measures and the sprint profile measurements of collegiate track and field athletes. METHODS: Twenty-five athletes (18 males and 7 females) completed two squat jump trials with a linear encoder attached to a 45 lbs. bar placed on the athlete’s upper back. Measures of interest during the concentric phase of the SJ included jump height, maximum force, maximum velocity, maximum power, and rate of force development. Athletes then completed two 30-meter acceleration sprints. The MySprint mobile application was used to acquire the athlete’s sprint profile and to assess maximal theoretical horizontal force, maximal theoretical velocity, optimal velocity, maximal theoretical power, maximal speed, maximal ratio of force, force-velocity slope, and decrease in ratio of force. The best trial was used for statistical analysis. Pearson’s or Spearman’s correlation coefficients were conducted between SJ measures and sprint profile measures. RESULTS: There was a positive correlation between SJ height and maximal speed (r = 0.402; p = 0.042). Maximal power during the SJ was positively correlated with maximal speed (r = 0.476; p = 0.014); optimal velocity (r = 0.469; p = 0.018); maximal theoretical power (r = 0.462; p = 0.018); maximal theoretical velocity (r = 0.452; p = 0.021); theoretical horizontal force (r = 0.431; p = 0.028); and maximal ratio force (r = 0.428; p = 0.029). Maximal velocity during the SJ was correlated with maximal speed (r = 0.519; p = 0.007); maximal theoretical velocity (r = 0.499; p = 0.010); optimal velocity (r = 0.486; p = 0.014); and maximal theoretical power (r = 0.484; p = 0.012). No other correlations were significant. CONCLUSION: Maximal velocity and power during the concentric phase of the SJ are moderately to strongly correlated with maximal sprinting speed, velocity, and power. SJ height is positively correlated with maximum sprint speed. There is a lack of significant correlations between other measures of the SJ and sprint profile measures. SJ power and velocity are correlated with sprint performance, therefore power and velocity improved through plyometric SJ training may be transferable to achieve better sprint performance