Richard S. Farley

THE EFFECT OF STATIC STRETCHING ON PHASES OF SPRINT PERFORMANCE IN ELITE SOCCER PLAYERS

Sayers, AL, Farley, RS, Fuller, DK, Jubenville, CB, and Caputo, JL. The effect of static stretching on phases of sprint performance in elite soccer players. J Strength Cond Res 22(5): 1416-1421, 2008-The purpose of this study was to determine which phase of a 30-m sprint (acceleration and/or maximal velocity) was affected by preperformance static stretching. Data were collected from 20 elite female soccer players. On two nonconsecutive days, participants were randomly assigned to either the stretch or no-stretch condition. On the first day, the athletes in the no-stretch condition completed a standard warm-up protocol and then performed three 30-m sprints, with a 2-minute rest between each sprint. The athletes in the stretch condition performed the standard warm-up protocol, completed a stretching routine of the hamstrings, quadriceps, and calf muscles, and then immediately performed three 30-m sprints, also with a 2-minute rest between each sprint. On the second day, the groups were reversed, and identical procedures were followed. One-way repeated-measures analyses of variance revealed a statistically significant difference in acceleration (p < 0.0167), maximal-velocity sprint time (p < 0.0167), and overall sprint time (p < 0.0167) between the stretch and no-stretch conditions. Static stretching before sprinting resulted in slower times in all three performance variables. These findings provide evidence that static stretching exerts a negative effect on sprint performance and should not be included as part of the preparation routine for physical activity that requires sprinting.

Occlusion training increases muscular strength in division IA football players.

Abstract Yamanaka, T, Farley, RS, and Caputo, JL. Occlusion training increases muscular strength in division IA football players. J Strength Cond Res 26(9): 2523–2529, 2012—The purpose of this study was to investigate the effectiveness of 4 weeks of low-intensity resistance training with blood-flow occlusion on upper and lower body muscular hypertrophy and muscular strength in National Collegiate Athletic Association Division IA football players. There were 32 subjects (average age 19.2 ± 1.8 years) who were randomized to an occlusion group or control group. The athletes performed 4 sets of bench press and squat in the following manner with or without occlusion: 30 repetitions of 20% predetermined 1 repetition maximum (1RM), followed by 3 sets of 20 repetitions at 20% 1RM. Each set was separated by 45 seconds. The training duration was 3 times per week, after the completion of regular off-season strength training. Data collected included health history, resting blood pressure, pretraining and posttraining bench press and squat 1RM, upper and lower chest girths, upper and lower arm girths, thigh girth, height, and body mass. The increases in bench press and squat 1RM (7.0 and 8.0%, respectively), upper and lower chest girths (3 and 3%, respectively), and left upper arm girth were significantly greater in the experiment group (p < 0.05). Occlusion training could provide additional benefits to traditional strength training to improve muscular hypertrophy and muscular strength in collegiate athletes.

The Relationship between Cortisol and Bone Mineral Density in Competitive Male Cyclists

Objective. The purpose of this study was to determine whether race day cortisol was related to bone mineral density (BMD) in competitive male cyclists. A secondary purpose was to determine additional factors associated with BMD in competitive male cyclists. Methods. Measurements of lumbar spine and hip BMD were performed in 35 male competitors in a state championship cycling time trial event. Salivary cortisol was measured 10 minutes prior to the start of the race and 5 minutes after race finished. Participants reported daily calcium intake, age, years of bike training, races per season, and average weekly minutes spent riding a bike, weight training, and running on a survey. Results. Cortisol level increased significantly from pre- to postcompetition but was not significantly associated with BMD. Increased weekly minutes of weight training was associated with higher BMD of the lumbar spine and the hip. The increased number of years of cycling experience was associated with lower BMD of the femoral neck. Increased daily calcium intake was associated with higher BMD of the lumbar spine and femoral neck. Conclusions. Findings indicate that cyclists should participate in weight training and increase calcium intake in order to increase or maintain BMD of the lumbar spine and hip.

Relative Age Effect Among Elite Youth Female Soccer Players across the United States

The consequence of relative age eff ect (RAE) has been an overrepresentation of athletes born early in the cohort and an underrepresentation of athletes born late in the cohort. There are signifi cantly fewer studies that examine this phenomenon among female soccer players. Therefore, the purpose was to determine the existence of RAEs among elite youth female soccer players competing in the Elite Clubs National League (ECNL) during the 2012-2013 season. Player birthdates (U14-U18 N=7,294) were collected from the ECNL and compared to the birthdates distribution for the general population. Data revealed a RAE across all age groups (U14-U18) indicating a preference for the selection of the oldest in the cohort. An overrepresentation of players was observed in Q1 and an underrepresentation of players in Q4 among the U14-U17 age groups. Among the u18 age group, an overrepresentation of players was detected in Q2 and an underrepresentation of players in Q4. The birthdate distribution for the fi rst and second halves of the playing season showed strong RAEs among the U14-U17 age groups. No statistically signifi cant diff erence was found between the fi rst and second halves of the playing season among players in the U18 age group.