Katie Small

The effects of multidirectional soccer-specific fatigue on markers of hamstring injury risk

The purpose of this work was to investigate the effect of multidirectional soccer-specific fatigue on hamstring muscle strength and angle of peak torque. Sixteen male semi-professional soccer players (mean+/-S.D.: age: 21.3+/-2.9 years; height 185.0+/-8.7 cm; body mass 81.6+/-6.7 kg) completed the SAFT(90), a multidirectional, intermittent 90-min exercise protocol based on data from English Championship soccer matches. Prior to exercise (t(0)), at half-time (t(45)) and post-exercise (t(105)), subjects performed three maximal dominant limb isokinetic contractions (Biodex, System 3) at 120 degrees s(-1) through a 90 degrees range for concentric and eccentric knee flexors and concentric knee extensors. Analysis of variance revealed significant time dependant reductions in gravity corrected eccentric hamstring peak torque, and consequently in the functional hamstring:quadriceps ratio (P<0.01). Eccentric hamstring peak torque decreased significantly during each half (t(0): 272.0+/-43.2; t(45): 240.4+/-43.3; t(105): 226.3+/-45.7 Nm). The functional hamstring:quadriceps ratio also decreased significantly during each half (t(0): 116.6+/-21.2; t(45): 107.1+/-17.6; t(105): 98.8+/-20.3%). There were no significant changes in concentric hamstring or quadriceps peak torque observed during SAFT(90) (P>0.05). Data analysis also revealed significant differences for Angle of Peak Torque for eccentric hamstrings (P<0.05) which was significantly higher at the end of each half (t(45): 37+/-15; t(105): 38+/-18 degrees ) than the pre-exercise value (t(0): 28+/-12 degrees ). There was a time dependant decrease in peak eccentric hamstring torque and in the functional strength ratio which may have implications for the increased predisposition to hamstring strain injury during the latter stages of match-play.

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.

Effects of different half-time strategies on second half soccer-specific speed, power and dynamic strength

This study compared the effects of whole body vibration (WBV) and a field‐based re‐warm‐up during half‐time (HT) on subsequent physical performance measures during a simulated soccer game. Ten semi‐professional male soccer players performed 90‐min fixed‐intensity soccer simulations (SAFT90), using a multi‐directional course. During the HT period players either remained seated (CON), or performed intermittent agility exercise (IAE), or WBV. At regular intervals during SAFT90, vastus lateralis temperature (Tm) was recorded, and players also performed maximal counter‐movement jumps (CMJ), 10‐m sprints, and knee flexion and extension contractions. At the start of the second half, sprint and CMJ performance and eccentric hamstring peak torque were significantly reduced compared with the end of the first half in CON (P≤0.05). There was no significant change in these parameters over the HT period in the WBV and IAE interventions (P>0.05). The decrease in Tm over the HT period was significantly greater for CON and WBV compared with IAE (P≤0.01). A passive HT interval reduced sprint, jump and dynamic strength performance. Alternatively, IAE and WBV at HT attenuated these performance decrements, with limited performance differences between interventions.

Effect of timing of eccentric hamstring strengthening exercises during soccer training: implications for muscle fatigability

Small, K, McNaughton, L, Greig, M, and Lovell, R. Effect of timing of eccentric hamstring strengthening exercises during soccer training: implications for muscle fatigability. J Strength Cond Res 23(4): 1077-1083, 2009-The purpose of this study was to examine the effects of a field-based injury prevention exercise on eccentric hamstring strength during simulated soccer match play. Sixteen semiprofessional soccer players (age 21.3 ± 2.9 years; height 185.0 ± 8.7 cm; body mass 81.6 ± 6.7 kg) completed the Soccer-specific Aerobic Field Test (SAFT90), a multidirectional 90-minute exercise protocol representative of soccer match play. Subjects performed 3 maximal dominant-limb isokinetic contractions at 120°·s−1 for concentric knee extensors (conQ) and flexors (conH), and eccentric knee flexors (eccH) before SAFT90 (t0), at half-time (t45), and immediately after the SAFT90 (t105). After baseline testing, subjects were divided into 2 groups, either performing Nordic hamstring eccentric strengthening exercises during the cool-down (CD) or warm-up (WU) of twice-weekly training sessions. After an 8-week intervention program, the baseline testing was repeated. The WU group displayed a significant increase postintervention in eccH gravity-corrected peak torque (PT) and the functional eccH:conQ ratio at t0 (p < 0.01), a significantly greater improvement compared with CD group (p < 0.05). Conversely, the CD group displayed a significant increase in both eccH PT and the functional eccH:conQ ratio postintervention at t45 (p < 0.05) and at t105 (p < 0.05), which were significantly greater increases compared with the WU group (p < 0.05). These findings indicate that the training intervention had a time-dependent beneficial effect on eccentric hamstring strength and that strength training conducted posttraining significantly reduced the negative influence of fatigue.

Musculoskeletal injury rates in multiday marathon runners performing ten consecutive marathons on a repeat course

Since 2015 I started reading Greek Philosophy and I visited many times the museum of Acropolis, Athens. I found really amazing the Myth of Greek God Hephaestus. His mother Hera when was infant, decided to throw it in the sea because he was ugly. This little kid raised by two other women. Hephaestus was married with the Goodness of beauty, Aphrodite but his marriage was a disaster, because he was violent to his wife.

MUSCULOSKELETAL INJURY RATES IN MULTIDAY MARATHON RUNNERS PERFORMING A REPEAT COURSE

Background Ultramarathon events are increasingly popular amongst non-elite athletes. However, there is little research investigating musculoskeletal injury rates, specifically multiday events using the same racing route. Objective To describe musculoskeletal injury rates in runners completing ten marathons over ten consecutive days. Design Observational. Setting Sports-injury clinic. Participants 27 athletes entered the study (age 45.1±7.47 yrs, mass 74.5±12.39 kg, years running 11.6±9.42 yrs, average weekly mileage 41.9±12.72 miles). 26 athletes completed all 10 marathons on a repeat, anti-clockwise, circular road course. One athlete withdrew due to serious injury. Main Outcome Measurements Musculoskeletal injuries were recorded by trained medical staff three times each day. An injury audit questionnaire was used to document injury rate, type and location. Injuries were defined as a specific musculoskeletal abnormality that the runner perceived to effect performance. Results 26 athletes sustained 108 injuries, averaging 4 injuries per athlete. 89% of injuries involved the lower extremity, 24.1% occurred in the foot, 18.5% the hip/buttock, 16.7% the ankle and 16.7% in the lower leg. The most common injuries were blisters (15.7%), Achilles tendinitis (11.1%), medial tibial stress syndrome (10.2%), iliotibial band syndrome (ITBS) (9.3%) and low back pain (LBP) (9.3%). 64.3% of injuries were sustained to the left limb. Chi-squared analysis revealed more injuries in days 1–3 than days 4–6 (p=0.013) and days 7–10 (p=0.001). Conclusions Lower extremity injuries are highly likely in multiday marathon running; the most common being blisters, Achilles tendinitis, medial tibial stress syndrome, ITBS and LBP. Athletes entering these events should engage in appropriate injury prevention programmes. The majority of injuries were sustained to the left limb and during the first three days. Multiday marathon event organisers should consider alternating route direction to reduce injury risk; potentially the result of prolonged, altered gait biomechanics. However, further investigation of injury risk factors using larger sample sizes is required.

The effect of running nine marathons in nine days on proprioception and balance

Background Multi-day running events are becoming increasingly popular with nonprofessional athletes. However, it is unknown how and when this type of event affects injury risk factors such as proprioception and balance. Objective To evaluate the effect of running one, five consecutive and nine consecutive marathons on joint position sense (JPS) and dynamic balance. Design Cross-sectional, observational study. Setting Sports-injury clinic. Participants 21 athletes completing the event (age 44.8±8.09 yrs, mass 74.4±13.14 kg, years running 10.4±7.39 yrs, average weekly mileage 44.8±12.09 miles) entered the study. Ten athletes completed the JPS testing and five athletes completed the dynamic balance testing. Assessment of Risk Factors Risk factors were assessed the day before the event (day zero) and then following completion of one (day one), five (day five) and nine (day nine) consecutive marathons. The independent variable was time. Main Outcome Measurements JPS error into flexion and extension, star-excursion balance test (SEBT) and number of injuries per runner. Results Friedmans ANOVAs indicated no effects of time on JPS into extension (p=0.94), dominant-leg anterior (p=0.52) or posterior-lateral (p=0.65) SEBT reach. JPS flexion error significantly decreased by 1.3° from day one to five (p=0.032). Non-dominant leg anterior, posterior-medial and posterior-lateral SEBT reaches significantly decreased from day zero to nine by 0.09% (p=0.043), 0.13% (p=0.043) and 0.17% (p=0.043) of leg length respectively. Dominant leg posterior-medial SEBT reach also significantly decreased by 0.12% of leg length (p=0.043) from day zero to nine. There were 4.2 injuries per runner. Conclusions The results suggest multi-day running events can cause over four lower limb injuries per runner and reduce dynamic balance ability. Nonprofessional athletes completing these events should be aware of this high injury occurrence and prepare appropriately. Injury prevention programmes incorporating dynamic balance may be recommended. However future studies with additional risk factors and larger sample sizes are needed to substantiate these findings.