Mettler S.,University of Birmingham |
Mettler S.,ETH Zurich |
Mitchell N.,English Institute of Sport |
Tipton K.D.,University of Birmingham
Medicine and Science in Sports and Exercise | Year: 2010
Purpose: To examine the influence of dietary protein on lean body mass loss and performance during short-term hypoenergetic weight loss in athletes. Methods: In a parallel design, 20 young healthy resistance-trained athletes were examined for energy expenditure for 1 wk and fed a mixed diet (15% protein, 100% energy) in the second week followed by a hypoenergetic diet (60% of the habitual energy intake), containing either 15% (∼1.0 g•kg) protein (control group, n = 10; CP) or 35% (∼2.3 g•kg) protein (high-protein group, n = 10; HP) for 2 wk. Subjects continued their habitual training throughout the study. Total, lean body, and fat mass, performance (squat jump, maximal isometric leg extension, one-repetition maximum (1RM) bench press, muscle endurance bench press, and 30-s Wingate test) and fasting blood samples (glucose, nonesterified fatty acids (NEFA), glycerol, urea, cortisol, free testosterone, free Insulin-like growth factor-1 (IGF-1), and growth hormone), and psychologic measures were examined at the end of each of the 4 wk. Results: Total (-3.0 ± 0.4 and-1.5 ± 0.3 kg for the CP and HP, respectively, P = 0.036) and lean body mass loss (-1.6 ± 0.3 and-0.3 ± 0.3 kg, P = 0.006) were significantly larger in the CP compared with those in the HP. Fat loss, performance, and most blood parameters were not influenced by the diet. Urea was higher in HP, and NEFA and urea showed a group × time interaction. Fatigue ratings and "worse than normal" scores on the Daily Analysis of Life Demands for Athletes were higher in HP. Conclusions: These results indicate that ∼2.3 g•kg or ∼35% protein was significantly superior to ∼1.0 g•kg or ∼15% energy protein for maintenance of lean body mass in young healthy athletes during short-term hypoenergetic weight loss. Copyright © 2010 by the American College of Sports Medicine.
Horsley I.G.,English Institute of Sport |
Fowler E.M.,University of Salford |
Rolf C.G.,Karolinska University Hospital
Journal of Orthopaedic Surgery and Research | Year: 2013
Background: In the literature, little is known about the level and pattern of rugby injuries. Of the shoulder injuries reported, 51% of these are caused during a tackle, and 65% of all match injuries affected the shoulder.Objective: The study aims to describe a sport-specific unique intra-articular shoulder pathology of professional rugby players, who presented with persistent pain and dysfunction despite physiotherapeutic treatment and rest.Method: This study is a retrospective analysis set at a university sports medicine clinic. Eighty-seven professional rugby players, referred by their professional medical team since they could no longer play, underwent shoulder arthroscopy between June 2001 and October 2007 due to persistent shoulder pain and dysfunction. All were full-time professional male rugby union and rugby league players. They all had failed conservative treatment for their complaint, and the diagnosis was unclear. Arthroscopic findings were used as a measure of main outcome.Results: The primary mechanism of injury was reported as direct tackling (56%; n = 49) followed in succession by falling onto the arm (10%; n = 8). However, in 30% of the cases, no definite injury could be recalled. The main operative finding was that most patients exhibited multiple shoulder pathologies, with 75% of cases presenting with two or more pathologies. A superior labrum anterior to posterior (SLAP) lesion was evident at arthroscopy in 72 of the 87 cases (83%), while rotator cuff tears were evident in 43% of cases (n = 37). One-third of all cases had a Bankart tear (n = 29), despite none of them reporting previous dislocations, while other labral tears, excluding SLAP tears, to the inferior or posterior labrum were present in 34% (n = 30) of the cohort.Conclusions: Repeated tackling, which is clearly rugby specific, is most likely to be responsible for most of these shoulder injuries, which upon arthroscopic examination, showed signs of mixed pathology. We suggest that an early arthroscopic investigation is valuable in this population in order to confirm treatable diagnosis on the painful shoulder and expedite a safe return to play. © 2013 Horsley et al.; licensee BioMed Central Ltd.
Ford P.R.,Liverpool John Moores University |
Yates I.,English Institute of Sport |
Williams A.M.,Liverpool John Moores University |
Williams A.M.,University of Sydney
Journal of Sports Sciences | Year: 2010
We examined the practice activities and instructional behaviours employed by 25 youth soccer coaches during 70 different practice sessions. We evaluated the extent to which these activities and behaviours differ from those shown in contemporary research to best facilitate skill acquisition. Nine coaches worked with the under-9 years age group and eight coaches each with the under-13 and under-16 years age groups; nine of those coaches were employed at the elite level, nine at the sub-elite level, and seven at the non-elite level. Coaches had players spend more time in activities that were deemed less relevant to soccer match performance, termed "training form" (e.g. physical training, technique and skills practices), than activities deemed more relevant, termed "playing form" (e.g. small-sided/conditioned games and phase of play activities). Coaches provided high levels of instruction, feedback, and management, irrespective of the activity in which players engaged. Few differences in practice activities and instructional behaviours were reported across skill and age groups, implying the absence of any notable age- or skill-related progression. Findings are discussed with reference to recent research in the areas of skill acquisition, motor learning, and expert performance. © 2010 Taylor & Francis.
Leeder J.,English Institute of Sport |
Glaister M.,St. Marys College |
Pizzoferro K.,University of Surrey |
Dawson J.,University of Surrey |
Pedlar C.,St. Marys College
Journal of Sports Sciences | Year: 2012
Sleep is known to be an important component of recovery from training, yet little is known about the quality and quantity of sleep achieved by elite athletes. The aim of the present study was to quantify sleep in elite athletes using wristwatch actigraphy. Individual nights of sleep from a cohort of Olympic athletes (n = 47) from various sports were analysed and compared to non-athletic controls (n = 20). There were significant differences between athletes and controls in all measures apart from 'time asleep' (p = 0.27), suggesting poorer characteristics of sleep in the athlete group. There was a significant effect of gender on 'time awake' (mean difference: 12 minutes higher in males; 95% likely range: 3 to 21 minutes) and 'sleep efficiency' (mean difference: 2.4 lower in males; 95% likely range: 0.1 to 4.8). Athletes showed poorer markers of sleep quality than an age and sex matched non-athletic control group (Sleep efficiency: 80.6 ± 6.4% and 88.7 ± 3.6%, respectively. Fragmentation Index: 36.0 ± 12.4 and 29.8 ± 9.0, respectively) but remained within the range for healthy sleep. This descriptive study provides novel data for the purpose of characterising sleep in elite athletes. © 2012 Copyright Taylor and Francis Group, LLC.
Osborne N.J.,University of Sheffield |
Gatt I.T.,English Institute of Sport
Acupuncture in Medicine | Year: 2010
These case reports describe the short-term benefits of dry needling in shoulder injuries in four international female volleyball athletes during a month-long intense competitive phase, using both replicable subjective and objective measures. Dry needling of scapulohumeral muscles was carried out. Range of movement, strength and pain were assessed before and after treatment, with a functional assessment of pain immediately after playing and overhead activity, using the short form McGill Pain Questionnaire. All scores were improved post-treatment and athletes were able to continue overhead activities. Previous studies have suggested that myofascial trigger points may cause significant functional weakness and reduced range of motion, with referred pain. Trigger point dry needling has been successful in treating athletes with myofascial pain and impingement symptoms but with only subjective improvement and not during a competitive phase. These cases support the use of dry needling in elite athletes during a competitive phase with short-term pain relief and improved function in shoulder injuries. It may help maintain rotator cuff balance and strength, reducing further pain and injury.