Martyn Matthews

A systematic review into the efficacy of static stretching as part of a warm-up for the prevention of exercise-related injury

A systematic review of the literature was undertaken to assess the efficacy of static stretching as part of the warm-up for the prevention of exercise-related injuries. Computer-aided literature search for articles post-1990 and pre-January 2008 related to static stretching and injury prevention using MEDLINE, SPORT Discus, PubMed, and ScienceDirect databases. All relevant randomised clinical trials (RCTs) and controlled clinical trials (CCTs) satisfying inclusion/exclusion criteria were evaluated by methodological assessment to score the studies using accredited criteria. Seven out of 364 studies met the inclusion/exclusion criteria. All four RCTs concluded that static stretching was ineffective in reducing the incidence of exercise-related injury, and only one of the three CCTs concluded that static stretching did reduce the incidence of exercise-related injury. Three out of the seven studies noted significant reductions in musculotendinous and ligament injuries following a static stretching protocol despite nonsignificant reductions in the all-injury risk. All RCTs scored over 50 points (maximum possible score = 100), whereas all CCTs scored under 45 points. There is moderate to strong evidence that routine application of static stretching does not reduce overall injury rates. There is preliminary evidence, however, that static stretching may reduce musculotendinous injuries.

Complex training in ice hockey: the effects of a heavy resisted sprint on subsequent ice-hockey sprint performance.

Matthews, MJ, Comfort, P, and Crebin, R. Complex training in ice hockey: the effects of a heavy resisted sprint on subsequent ice-hockey sprint performance. J Strength Cond Res 24(11): 2883-2887, 2010-The aim of the study was to investigate the acute effect of a heavy resisted sprint when used as a preload exercise to enhance subsequent 25-m on-ice sprint performance. Eleven competitive ice-hockey players (mean ± SD: Age = 22.09 ± 3.05 years; Body Mass = 83.47 ± 11.7 kg; Height = 1.794 ± 0.060 m) from the English National League participated in a same-subject repeated-measures design, involving 2 experimental conditions. During condition 1, participants performed a 10-second heavy resisted sprint on ice. Condition 2 was a control, where participants rested. An electronically timed 25-m sprint on ice was performed before and 4 minutes after each condition. The results indicated no significant difference (p = 0.176) between pre (3.940 + 0.258 seconds) and post (3.954 + 0.261 seconds) sprint times in the control condition. The intervention condition, however, demonstrated a significant 2.6% decrease in times (p = 0.02) between pre (3.950 + 0.251 seconds) and post (3.859 + 0.288 seconds) test sprints. There was also a significant change (p = 0.002) when compared to the times of the control condition. These findings appear to suggest that the intensity and duration of a single resisted sprint in this study are sufficient to induce an acute (after 4 minutes of rest) improvement in 25-m sprint performance on ice. For those athletes wishing to improve skating speed, heavy resisted sprints on ice may provide a biomechanically suitable exercise for inducing potentiation before speed training drills.

Strength and Power Characteristics in English Elite Rugby League Players

Comfort, P, Graham-Smith, P, Matthews, MJ, and Bamber, C. Strength and power characteristics in English elite rugby league players. J Strength Cond Res 25(5): 1374-1384, 2011-The aim of this article is to present data on the strength and power characteristics of forwards and backs in a squad of elite English rugby league players and compare these findings to previously published literature from Australia. Participants were elite English rugby league players (n = 18; height 184.16 ± 5.76 cm; body mass 96.87 ± 10.92 kg, age 21.67 ± 4.10 years) who were all regular first team players for an English Superleague club. Testing included 5-, 10-, 20-m sprint times, agility, vertical jump, 40-kg squat jump, isometric squat, concentric and eccentric isokinetic knee flexion and extension. Independent t-tests were performed to compare results between forwards and backs, with paired samples t-tests used to compare bilateral differences from isokinetic assessments and agility tests. Forwards demonstrated significantly (p < 0.05) greater body mass (102.15 ± 7.5 kg), height (186.30 ± 5.47 cm), power during the 40-kg jump squat (2,106 ± 421 W), isometric force (3,122 ± 611 N) and peak torque during left concentric isokinetic knee extension (296.1 ± 54.2 N·m) compared to the backs (86.30 ± 8.97 kg; 179.87 ± 3.72 cm; 1,709 ± 286 W; 2,927 ± 607 N; 241.7 ± 35.2 N·m, respectively). However, no significant differences (p > 0.05) were noted between forwards and backs during right concentric isokinetic knee extension (274.8 ± 37.7 and 246.8 ± 25.8 N·m), concentric isokinetic knee flexion for both left (158.8 ± 28.6 and 141.0 ± 22. 7 N·m) and right legs (155.3 ± 22.9 and 128.0 ± 23.9 N·m), eccentric isokinetic knee flexion and extension, hamstring quadriceps ratios, or vertical jump (37.25 ± 4.35 and 40.33 ± 6.38 cm). In comparison, relative measures demonstrated that backs performed significantly better compared to the forwards during the 40-kg jump squat (20.71 ± 5.15 and 19.91 ± 3.91 W·kg−1) and the isometric squat (34.32 ± 7.9 and 30.65 ± 5.34 N·kg−1). Bilateral comparisons revealed no significant differences (p > 0.05) between left and right leg performances in the agility test (3.26 ± 0.18 and 3.24 ± 0.18 seconds), or between left (0.7 ± 0.10) and right (0.71 ± 0.17) leg eccentric hamstring concentric quadriceps ratios. The results demonstrate that absolute strength and power measures are generally higher in forwards compared to in backs; however, when body mass is taken into account and relative measures compared, the backs outperform the forwards.

The Acute Effects of a Resistance Training Warmup on Sprint Performance

Twenty male rugby union players were tested to determine the acute effect of a resistance training warmup on subsequent 20-m sprint performance. The study consisted of a repeated measures design with two experimental conditions. During the control (C) condition, the participants performed a 20-m sprint, rested for 10min, and then repeated the 20-m sprint. During the experimental (E) condition, the second sprint was preceded by five repetitions of a back-squat with a load equal to each participants five repetition maximum (5RM). Sprint times were recorded using New Test digital recording equipment. The results showed a mean improvement of 0.098s (p<0.0001) when the second sprint was preceded by the back squats. This amounted to a 3.3% improvement on the precondition time. During the control condition, no improvement was observed between the first and second sprint. The improved sprint times observed during the E condition probably were due to a temporary increase in the efficiency of neuromuscular activation following the performance of heavy-load back squats.

Angle-Specific Eccentric Hamstring Fatigue After Simulated Soccer

PURPOSE To evaluate the effect of simulated soccer on the hamstrings eccentric torque-angle profile and angle of peak torque (APTeccH), and on the hamstrings:quadriceps torque ratio at specific joint angles (ASHecc:Qcon). METHODS The authors assessed dominant-limb isokinetic concentric and eccentric knee flexion and concentric knee extension at 120°/s in 9 semiprofessional male soccer players immediately before and after they completed the Loughborough Intermittent Shuttle Test (LIST). RESULTS The LIST resulted in significant decreases in eccentric hamstrings torque at 60°, 50°, and 10° and a significant (21.8%) decrease in ASHecc:Qcon at 10° (P < .05). APTeccH increased from 7.1° ± 1.0° to 18.8° ± 4.2° (P < .05). Eccentric hamstrings peak torque significantly declined from 185.1 ± 70.4 N·m pre-LIST to 150.9 ± 58.5 N·m post-LIST (P = .002), but there were no significant changes in hamstrings or quadriceps concentric peak torque (P = .312, .169, respectively). CONCLUSIONS Simulated soccer results in a selective loss of eccentric hamstrings torque and hamstrings-to-quadriceps muscle balance at an extended joint position and a shift in the eccentric hamstrings APT to a shorter length, changes that could increase vulnerability to hamstrings injury. These findings suggest that injury-risk screening could be improved by evaluating the eccentric hamstrings torque-angle profile and hamstrings strength-endurance and that the development of hamstrings fatigue resistance and long-length eccentric strength may reduce injury incidence.

Effects of strength training on squat and sprint performance in soccer players

Abstract Styles, WJ, Matthews, MJ, and Comfort, P. Effects of strength training on squat and sprint performance in soccer players. J Strength Cond Res 30(6): 1534–1539, 2016—Researchers have demonstrated that increases in strength result in increases in athletic performance, although the development of strength is still neglected in some sports. Our aim was to determine whether a simple in-season strength training program would result in increases in maximal squat strength and short sprint performance, in professional soccer players. Professional soccer players (n = 17, age = 18.3 ± 1.2 years, height = 1.79 ± 0.06 m, body mass [BM] = 75.5 ± 6.1 kg) completed 1 repetition maximum (1RM) back squat and sprint tests (5, 10, and 20 m) before and after a 6-week (×2 week) in-season strength training (85–90% 1RM) intervention. Strength training resulted in significant improvements in absolute and relative strength (before = 125.4 ± 13.8 kg, after = 149.3 ± 16.2 kg, p ⩽ 0.001, Cohens d = 0.62; 1RM/BM before: 1.66 ± 0.24 kg·kg−1, after = 1.96 ± 0.29 kg·kg−1, p ⩽ 0.001, Cohens d = 0.45; respectively). Similarly, there were small yet significant improvements in sprint performance over 5 m (before = 1.11 ± 0.04 seconds, after = 1.05 ± 0.05 seconds, p ⩽ 0.001, Cohens d = 0.55), 10 m (before = 1.83 ± 0.05 seconds, after = 1.78 ± 0.05 seconds, p ⩽ 0.001, Cohens d = 0.45), and 20 m (before = 3.09 ± 0.07 seconds, after = 3.05 ± 0.05 seconds, p ⩽ 0.001, Cohens d = 0.31). Changes in maximal squat strength seem to be reflected in improvements in short sprint performance highlighting the importance of developing maximal strength to improve short sprint performance. Moreover, this demonstrates that these improvements can be achieved during the competitive season in professional soccer players.

Training Considerations after Hamstring Injury in Athletes

HAMSTRING STRAINS ARE COMPOUNDED BY A HIGH RECURRENCE RATE OF 12-31% WITHIN THE FIRST YEAR OF RETURN TO SPORT. EXPLANATIONS INCLUDE REDUCED TENSILE STRENGTH, REDUCED STRENGTH OF MUSCLE AND SURROUNDING SITES, AND REDUCED FLEXIBILITY OF THE MUSCLE TENDON UNIT. STRETCHING ALONE IS INSUFFICIENT FOR COMPLETE REHABILITATION, RESULTING IN A RECURRENCE RATE AS HIGH AS 54.5% WITHIN 2 WEEKS OF RETURN TO SPORT. SPORT-SPECIFIC EXERCISE HAS BEEN SHOWN TO BE MORE SUCCESSFUL. FOR COMPLETE REHABILITATION OF HAMSTRING STRAIN, THE INCLUSION OF ECCENTRIC PLYOMETRIC EXERCISE AND SPORT SPECIFIC DRILLS AT THE APPROPRIATE TIME IS ESSENTIAL.

Applying complex training principles to boxing: A practical approach

THIS ARTICLE DISCUSSES THE APPLICATION OF COMPLEX TRAINING PRINCIPLES IN THE DEVELOPMENT OF SPEED AND POWER IN BOXING. IN IT, WE ILLUSTRATE HOW THE ADDITION OF EXTERNAL RESISTANCE, APPLIED IN BIOMECHANICALLY SIMILAR WAYS TO TRADITIONAL BOXING SKILLS AND INCORPORATED BEFORE EACH TRADITIONAL BOXING TRAINING SET, CAN HAVE A POTENTIATION EFFECT, RESULTING IN SUBJECTIVELY OBSERVED INCREASES IN PERFORMANCE. IT IS ALSO HOPED THAT THIS ARTICLE MAY STIMULATE ADDITIONAL RESEARCH IN THIS AREA.

A Comparison of Ratings of Perceived Exertion During Deep Water Running and Treadmill Running: Considerations in the Prescription of Exercise Intensity

Deep water running (DWR) is a form a aquatic exercise that simulates the action of land based running (LBR), but appears to cause less musculo-skeletal stress. Consequently, it has become a popular training modality for athletes recovering from injury. The psychophysical effects of DWR and LBR respectively were investigated at three exercise intensities. Maximum heart rate (HR max ) was established using a Cooper 1.5 mile run test and the Karvonen Heart Rate Reserve (HRR) method was used to calculate exercise intensity at 60%, 70%, and 80% HRR, respectively. Six males and four females with a mean age (‐SD) of 28.1 ‐ 4.9 years and unfamiliar with DWR undertook a 30-minute test in both DWR and LBR conditions. Each test consisted of 3 x 10 minute periods at 60%, 70%, and 80% HRR respectively. Rating of Perceived Exertion (RPE) was recorded during the last minute of each period. A difference in RPE was found between LBR and DWR at 60% (11.4 Vs 12.8, p < 0.001), 70% (12.9 Vs 15.2, p < 0.001), and 80% HRR (14.5 Vs 17.7, p < 0.001). A significant difference in RPE was attributed to localized fatigue associated with the unfamiliarity of the task, reflected by increased cardiovascular stress at any given heart rate. Athletes and trainers should exhibit caution when prescribing a specific DWR exercise intensity based on HR max date obtained from a land based test. A downward adjustment of 12n17 beats per minute is considered prudent to ensure that exercise intensity is appropriate to the goal of the training program and to the traineeis current ability.

The assisted nordic hamstring curl

Assisted nordic hamstring curls provide a mechanism for assisting the lower phases of a nordic hamstring curl, allowing training at increased hamstring muscle length positions and the performance of more repetitions. This exercise may be useful to target the specific muscle lengths or fatigue conditions at which injuries occur.