Jay J. Dawes

Relationship of Two Vertical Jumping Tests to Sprint and Change of Direction Speed among Male and Female Collegiate Soccer Players

In collegiate level soccer acceleration, maximal velocity and agility are essential for successful performance. Power production is believed to provide a foundation for these speed qualities. The purpose of this study was to determine the relationship of change of direction speed, acceleration, and maximal velocity to both the counter movement jump (CMJ) and squat jump (SJ) in collegiate soccer players. Thirty-six NCAA Division II soccer players (20 males and 16 females) were tested for speed over 10 and 30 m, CODS (T-test, pro agility) and power (CMJ, SJ). Independent t-tests (p ≤ 0.05) were used to derive gender differences, and Pearson’s correlations (p ≤ 0.05) calculated relationships between the different power and speed tests. Female subjects displayed moderate-to-strong correlations between 30 m, pro agility and T-test with the CMJ (r = −0.502 to −0.751), and SJ (r = −0.502 to −0.681). Moderate correlations between 10 and 30 m with CMJ (r = −0.476 and −0.570) and SJ (r = −0.443 and −0.553, respectively) were observed for males. Moderate to strong relationships exist between speed and power attributes in both male and female collegiate soccer players, especially between CMJ and maximal velocity. Improving stretch shortening cycle (SSC) utilization may contribute to enhanced sport-specific speed.

The use of 2 conditioning programs and the fitness characteristics of police academy cadets

CONTEXT  Police academy training must physically prepare cadets for the rigors of their occupational tasks to prevent injury and allow them to adequately perform their duties. OBJECTIVE  To compare the effects of 2 physical training programs on multiple fitness measures in police cadets. DESIGN  Cohort study. SETTING  Police training academy. PATIENTS OR OTHER PARTICIPANTS  We collected data from 70 male (age = 27.4 ± 5.9 years, body weight = 85.4 ± 11.8 kg) and 20 female (age = 30.5 ± 5.8 years, body weight = 62.8 ± 11.0 kg) police cadets and analyzed data from 61 male cadets (age = 27.5 ± 5.5 years, body weight = 87.7 ± 13.2 kg). INTERVENTION(S)  Participants completed one of two 6-month training programs. The randomized training group (RTG; n = 50), comprising 4 separate and sequential groups (n = 13, n = 11, n = 13, n = 13), completed a randomized training program that incorporated various strength and endurance exercises chosen on the day of training. The periodized group (PG; n = 11) completed a periodized training program that alternated specific phases of training. MAIN OUTCOME MEASURE(S)  Anthropometric fitness measures were body weight, fat mass, and lean body mass. Muscular and metabolic fitness measures were 1-repetition maximum bench press, push-up and sit-up repetitions performed in 1 minute, vertical jump, 300-m sprint, and 2.4-km run. RESULTS  The RTG demonstrated improvements in all outcome measures between pretraining and posttraining; however, the improvements varied among the 4 individual RTGs. Conversely, the PG displayed improvements in only 3 outcome measures (push-ups, sit-ups, and 300-m sprint) but approached the level of significance set for this study (P < .01) in body weight, fat mass, and 1-repetition maximum bench press. CONCLUSIONS  Regardless of format, physical training programs can improve the fitness of tactical athletes. In general, physical fitness measures appeared to improve more in the RTG than in the PG. However, this observation varied among groups, and injury rates were not compared.

Relationships between Linear Speed and Lower-Body Power with Change-of-Direction Speed in National Collegiate Athletic Association Divisions I and II Women Soccer Athletes

This study investigated relationships that linear speed and lower-body power have on change-of-direction (COD) speed in collegiate women soccer players. Data from two Division I (n = 39) and one Division II (n = 18) schools were analyzed. Subjects were assessed in: power (vertical jump (VJ); jump height, peak anaerobic power measured in watts (PAPw), power-to-body mass ratio (P:BM); linear speed (10-m sprint); and COD speed (modified T-test (MTT), 505, COD deficit). Independent samples T-tests derived significant between-group differences, with effect sizes (d) calculated. Pearson’s correlations determined relationships between COD speed, linear speed, and power, with regression equations calculated. Division I players demonstrated superior 505, COD deficit, VJ height, PAPw, and P:BM (d = 1.09–2.21). Division II players were faster in the MTT (d = 1.51). For all players, the 505 correlated with the 10-m sprint (r = 0.39–0.53) and VJ height (r = −0.65–0.66), while the COD deficit related to the 10-m sprint (r = −0.77–0.82). The regression data supported these results. Division I players were superior in the 505 and COD deficit, and expressed their power in the 180° 505 task. Division II players should enhance lower-body power and the ability to perform 180° direction changes.

Relationship of Absolute and Relative Lower-Body Strength to Predictors of Athletic Performance in Collegiate Women Soccer Players

The purpose of this study was to investigate the relationships between absolute and relative lower-body strength on predictors of athletic performance among Division II collegiate women’s soccer players. Archived pre-season testing data for seventeen (n = 17) female National Collegiate Athletics Association (NCAA) Division II soccer players were analyzed, including: vertical jump, 3RM back squat, 505-agility, modified T-test, 10 m and 30 m sprint, and 20 m multistage fitness test (20 m MSFT). Relative strength was calculated based on the estimated 1RM back squat divided by the athlete’s body mass. Significant correlations were discovered between absolute lower-body strength and 505-agility (Right: r = −0.51, p < 0.05; Left: r = −0.59, p < 0.05), modified T-test (r = −0.55, p < 0.05), 10 m and 30 m (r = −0.59, p < 0.05; r = −0.54, p < 0.05), and sprint performance. Relative lower-body strength showed significant correlations with vertical jump (r = 0.54, p < 0.05), 505-agility (Right: r = −0.58, p < 0.05; Left: r = −0.67, p < 0.01), modified T-test (r = −0.75, p < 0.01), 10 m and 30 m (r = −0.59 p < 0.05; r = −0.67, p < 0.01), and the 20 m MSFT (r = 0.58, p < 0.05). These results indicate that strength and conditioning coaches should emphasize the development of absolute and relative lower-body strength with their players to improve power, agility, and speed performance.

The Impact of Load Carriage on Measures of Power and Agility in Tactical Occupations: A Critical Review

The current literature suggests that load carriage can impact on a tactical officer’s mobility, and that survival in the field may rely on the officer’s mobility. The ability for humans to generate power and agility is critical for performance of the high-intensity movements required in the field of duty. The aims of this review were to critically examine the literature investigating the impacts of load carriage on measures of power and agility and to synthesize the findings. The authors completed a search of the literature using key search terms in four databases. After relevant studies were located using strict inclusion and exclusion criteria, the studies were critically appraised using the Downs and Black Checklist and relevant data were extracted and tabled. Fourteen studies were deemed relevant for this review, ranging in percentage quality scores from 42.85% to 71.43%. Outcome measures used in these studies to indicate levels of power and agility included short-distance sprints, vertical jumps, and agility runs, among others. Performance of both power and agility was shown to decrease when tactical load was added to the participants. This suggests that the increase in weight carried by tactical officers may put this population at risk of injury or fatality in the line of duty.

A Description and Comparison of Cardiorespiratory Fitness Measures in Relation to Pitching Performance Among Professional Baseball Pitchers

The purpose of this study is to provide descriptive and comparative information regarding the cardiorespiratory fitness of professional baseball pitchers. Twenty-four (n = 24) major league (ML) baseball pitchers (starters n = 14; relievers n = 10) over seven seasons (2007–2013) were evaluated. A modified Bruce protocol and the CardioCoach™ CO2 metabolic analyzer were used to estimate VO2 max and anaerobic threshold (AT) at the beginning of each season. Performance data from each season was utilized to draw inference about pitching performance. One-way Analysis of Variance (ANOVA) was used to compare Starting (S) and Relief (R) pitchers above/below the group mean for VO2 max and AT. Pearson product moment correlations were also used to examine relationships between cardiorespiratory fitness and performance. Significant differences in performance were discovered between S pitchers above/below the overall group mean for VO2 max. (p ≤ 0.05) and for AT in Walks plus Hits per Inning Pitched (WHIP) (p ≤ 0.05) and Earned Run Average (ERA) (p ≤ 0.05). Significant relationships between VO2 max and Walks per 9 Innings (BB/9) (p ≤ 0.05), Home Runs per 9 innings (HR/9) (p ≤ 0.05), Wins (W) (p ≤ 0.05), Fielding Independent Pitching (FIP) (p ≤ 0.01), Strikeouts (K) (p ≤ 0.01), Hits per 9 innings (H/9) (p ≤ 0.01), Strikeouts per 9 innings (K/9) (p ≤ 0.01), ERA (p ≤ 0.01), and WHIP (p ≤ 0.01). Low, but significant, correlations were discovered between AT and WHIP (p ≤ 0.05) and ERA (≤0.05). CONCLUSION: Higher aerobic capacity appears to be more influential for S than R pitchers. Strength and conditioning practitioners should ensure that pitchers, especially S pitchers at the ML level, perform sufficient and appropriate endurance training to support pitching performance.