Sleep Restriction in Elite Soccer Players: Effects on Explosive Power, Wellbeing, and Cognitive Function.

Purpose: To investigate the cognitive, physical, and perceptual effects of sleep restriction (SR) in soccer players following a night match. Methods: In a crossover design, nine male soccer players from the English Premier League 2 (age, 21 ± 5 years; height, 1.80 ± 0.75 m; body mass, 74.2 ± 6.8 kg) recorded their sleep quality and quantity with sleep logs and a subjective survey after two night matches (19:00); one where sleep duration was not altered (CON) and one where sleep was restricted by a later bed-time (SR). Countermovement jump height (CMJ), subjective wellbeing (1-5 likert scale for mood, stress, fatigue, sleep, and soreness), and cognitive function were measured at baseline and the morning following the match (+12 h; M + 1). Results: Bed-time was later in SR than CON (02:36 ± 0.17 vs. 22:43 ± 29; P = .0001; ηp2 = 0.999) and sleep duration was shorter in SR than CON (5.37 ± 0.16 vs. 8.59 h ± 0.36; P = .0001; ηp2 = 0.926). CMJ decreased by ~8% after the match in both SR and CON (P = .0001; ηp2 = 0.915) but there were no differences between the conditions (P > .05; ηp2 = 0.041-0.139). Wellbeing was rated worse after both matches (P = .0001; ηp2 = 0.949) but there were no differences between the trials (P > .05; ηp2 = 0.172-257). SR did not influence cognitive function (P > .05; interaction effects, ηp2 = 0.172-257). Conclusion: SR following a nighttime soccer match does not impair CMJ performance, subjective wellbeing, or cognitive function the following morning.

Mobility in Community Dwelling Older Adults: Predicting Successful Mobility Using an Instrumented Battery of Novel Measures.

Mobility in older adults is associated with better quality of life. However, evidence suggests that older people spend less time out-of-home than younger adults. Traditional methods for assessing mobility have serious limitations. Wearable technologies provide the possibility of objectively assessing mobility over extended periods enabling better estimates of levels of mobility to be made and possible predictors to be explored. Eighty-six community dwelling older adults (mean age 79.8 years) had their mobility assessed for one week using GPS, accelerometry and self-report. Outcomes were: number of steps, time spent in dynamic outdoor activity, total distance travelled and total number of journeys made over the week. Assessments were also made of personal, cognitive, psychological, physical and social variables. Four regression models were calculated (one for each outcome). The models predicted 32 to 43% of the variance in levels of mobility. The ability to balance on one leg significantly predicted all four outcomes. In addition, cognitive ability predicted number of journeys made per week and time spent engaged in dynamic outdoor activity, and age significantly predicted total distance travelled. Overall estimates of mobility indicated step counts that were similar to those shown by previous research but distances travelled, measured by GPS, were lower. These findings suggest that mobility in this sample of older adults is predicted by the ability to balance on one leg. Possible interventions to improve out-of-home mobility could target balance. The fact that participants travelled shorter distances than those reported in previous studies is interesting since this high-functioning subgroup would be expected to demonstrate the highest levels.

The impact of blackcurrant juice on attention, mood and brain wave spectral activity in young healthy volunteers.

There is a growing body of evidence from randomized controlled trials which indicates that consumption of berries has a positive effect upon the cognitive function of healthy adults. It has been recommended that studies combining cognitive and physiological measures be undertaken in order to strengthen the evidence base for the putative effects of flavonoid consumption on cognitive outcomes. This pilot study utilized a randomized, double-blind and placebo controlled crossover design to assess the influence of the acute administration of anthocyanin-rich blackcurrant juice, standardized at 500 mg of polyphenols, on mood and attention. Additionally, this trial used electroencephalography (EEG) to assess if any changes in cognitive performance are associated with changes in localized prefrontal cortex neuronal activity in nine healthy young adults. Outcomes from the pilot EEG data highlight an anxiolytic effect of the consumption of a single serve blackcurrant juice, as indexed by a suppression of α spectral power, and an increase in the slow wave δ and θ spectral powers. There was also an indication of greater alertness and lower fatigue, as indexed by an increase in ß power and suppression of α spectral power. Outcomes from the CogTrack™ system indicated a small acute increase in reaction times during the digit vigilance task.

Protein for Life: Towards a focussed dietary framework for healthy ageing.

'Ageing well' has been highlighted as an important research area by the World Health Organization. In the UK, healthy ageing has been identified as a priority research area by multiple Research Councils and is a key NHS priority. Sarcopaenia, the decline of muscle mass/strength and a key component of healthy ageing, can have a major impact on quality of life and is associated with premature mortality. Increasing protein intake at all stages of the life course may help to reduce the rate of muscle decline and the onset of associated health conditions. However, there is a lack of understanding of the social, demographic and psychological drivers of food choices surrounding protein intake. This report describes the multidisciplinary approach that has been adopted by the Protein for Life project to create a framework for the development of palatable, cost-effective higher-protein foods suitable for an ageing population.

Erratum to: Cognitive and mood improvements following acute supplementation with purple grape juice in healthy young adults.

In the original publication of the article, on page 7, paragraph "Discussion", line 12, 'blackcurrant has been observed to increase digit vigilance reaction time' should read as 'blackcurrant has been observed to decrease digit vigilance reaction time'.

Cognitive and mood improvements following acute supplementation with purple grape juice in healthy young adults.

PURPOSE: Berry-derived phenolic compounds found in grapes have been associated with a number of health benefits, including the augmentation of human brain function and cognition. Previous intervention studies of Concord grape juice have demonstrated improvement to memory and driving ability following 3- to 4-month supplementation in middle-aged and older adults. However, no studies to date have demonstrated acute cognitive benefits of grape juice, and investigation of these effects in young adults is lacking. METHODS: This randomised, placebo-controlled, double-blind, counterbalanced-crossover study, assessed the effects of 230 ml purple grape juice or sugar-matched control in 20 healthy young adults. Computerised measures of episodic memory, working memory, attention and mood were completed at baseline and following a 20-min absorption period. RESULTS: Purple grape juice significantly improved reaction time on a composite attention measure (p = 0.047) and increased calm ratings (p = 0.046) when compared to placebo. Order effects also indicated an enduring positive effect on pre-dose memory reaction time (p = 0.018) and post-dose calm ratings (p = 0.019) when purple grape was consumed first. CONCLUSIONS: These findings in a small sample of healthy young adults suggest that purple grape juice can acutely enhance aspects of cognition and mood. No significant effects of juice were observed on memory measures, suggesting that these may be less susceptible to manipulation following acute supplementation in healthy young adults. Potential mechanisms underlying these effects include modulation of cerebral blood flow, glucoregulation and inhibition of monoamine oxidase activity, all of which require further exploration.

Chemical composition and tissue energy density of the cuttlefish (Sepia apama) and its assimilation efficiency by Diomedea albatrosses.

The cuttlefish Sepia apama Gray (Mollusca: Cephalopoda) is a seasonally abundant food resource exploited annually by moulting albatrosses throughout winter and early spring in the coastal waters of New South Wales, Australia. To assess its nutritional value as albatross forage, we analysed S. apama for water, lipid protein, ash contents, energy density and amino acid composition. Because albatrosses consistently consume S. apama parts preferentially in the order of head, viscera and mantle, we analysed these sections separately, but did not identify any nutritional basis for this selective feeding behaviour. The gross energy value of S. apama bodies was 20.9 kJ/g dry mass, but their high water content (>83%; cf <70% for fish) results in a relatively low energy density of 3.53 kJ/g. This may contribute to a need to take large meals, which subsequently degrade flight performance. Protein content was typically >75% dry mass, whereas fat content was only about 1%. Albatrosses feed on many species of cephalopods and teleost fish, and we found the amino acid composition of S. apama to be comparable to a range of species within these taxa. We used S. apama exclusively in feeding trials to estimate the energy assimilation efficiency for Diomedea albatrosses. We estimated their nitrogen-corrected apparent energy assimilation efficiency for consuming this prey to be 81.82 ± 0.72% and nitrogen retention as 2.90 ± 0.11 g N kg(-1) d(-1). Although S. apama has a high water content and relatively low energy density, its protein composition is otherwise comparable to other albatross prey species. Consequently, the large size and seasonal abundance of this prey should ensure that albatrosses remain replete and adequately nourished on this forage while undergoing moult.

Sports injuries related to flexibility, posture, acceleration, clinical defects, and previous injury, in high-level players of body contact sports.

One-hundred-and-two high-level players of the field-games soccer, Gaelic football and hurling began a two-year investigation into the intrinsic causes of sports-injuries; 86 completed the study. During the first year all injuries, and the time affected by injury, were recorded. The subjects then underwent flexibility tests, an accurate photogrammetric assessment of posture, measures of speed and acceleration, and a clinical assessment of anatomical and physiological factors thought to be associated with the risk of sports injury. Time affected by injury was then recorded for a further 12-month period. Stepwise multiple-regression analysis revealed that the number of days of injury during the second 12-month period could be predicted from (1) the days of injury during the first 12-month period, (2) posture, (3) acceleration over 10m from a standing start, and (4) the number of musculo-skeletal clinical defects. Flexibility scores were not found to be significant predictors of injury. It is suggested that injury prevention programmes should concentrate on improving posture and the rehabilitation from previous injury rather than flexibility; and that research should be undertaken into the effectiveness of such interventions.

A reliable technique for the assessment of posture: assessment criteria for aspects of posture.

BACKGROUND: The purposes of this study were: a) to describe assessment criteria for 10 separate aspects of posture; b) to describe the development and use of a qualitative posture rating scale based on the above; and c) to establish the reliability of the assessment technique. METHODS: Experimental design. Observation and photographic record of the posture of a sample of adolescent males. Reliability determined using two observations separated by a period of seven days. PARTICIPANTS: 114 adolescent males (age, 15-17 yrs) randomly selected from two post-primary schools. MEASURES: Ten different aspects of posture assessed according to defined criteria. Assessments made from four photographs: anterior, posterior, lateral and oblique views. RESULTS: Through examination of the photographs a qualitative postural assessment scale was developed. This consisted of three categories for each aspect of posture, corresponding to: good posture, moderate defect, and severe defect. Definite assessment criteria for each of the 10 aspects of posture have been described. The above has resulted in an assessment procedure in which the reproducibility of the posture scores exceeded 85 % for all aspects assessed. CONCLUSIONS: Definite criteria for the examination of 10 different aspects of posture have been described and clear diagrams representing good posture, moderate and severe defects have been produced. The reproducibility of the assessment procedure described makes it suitable for investigating the relationships between posture and other health variables such as musculo-skeletal disorders.

Ankle sprains in players of the field-games Gaelic football and hurling.

BACKGROUND: The objectives of the study were to determine the most common injuries in Gaelic football and hurling and to quantify contributory factors. HYPOTHESIS: The hypothesis tested was "Ankle sprains are a common injury in Gaelic football and hurling and their incidence can be linked to physical characteristics of the players". EXPERIMENTAL DESIGN: prospective study over four years. SUBJECTS: eighty male players of Gaelic football, and hurling, aged 18-27 years. MEASURES: the injuries sustained over a four-year period. Physical fitness tests and examination at the start of the study which included assessment of: anthropometric variables, lower-limb proprioception, lung function, six aspects of flexibility, 15 aspects of posture and body mechanics. RESULTS: 962 significant sports injuries which included: 218 strains and 184 sprains. 122 were ankle sprains; 79 to the left ankle and 43 to the right. 104 ankle sprains represented a recurrence of this injury in a particular individual. In 26 out of 34 of these subjects both ankles were involved. This suggests that recurrence is not primarily due to previous injury but to intrinsic factors in the subjects that predispose them to ankle sprain. The subjects who sustained ankle sprains had (1) greater height, (2) lower body mass index (3) a higher incidence of posture defects of the ankle and knee, (4) more clinical defects (5) a higher incidence of defective lower-limb proprioception. CONCLUSIONS: Ankle sprains are a common injury. Their incidence is linked to the five intrinsic factors listed above.

A twelve month study of sports injuries in one Irish school.

A literature review suggested that both acute and overuse injuries were common in body contact sports. This hypothesis was tested on a group of 266 Irish adolescents in an investigation that examined the incidence of injury amongst these individuals over a twelve months period. The mean age of the subjects was:- males 14.3 +/- 0.85 years and females 14.1 +/- 0.90 years. The responses of the subjects to a questionnaire on their sporting involvement, training and sports injuries were analysed. A total of 230 injuries were incurred by the subjects during the twelve month period: 181 of these were to males. However, the number of injuries per hour of participation was similar in the two sexes. Subjects involved in body contact sports incurred the highest number of overuse injuries. The injury rate per 10,000 hours of participation was highest in badminton (70.85 injuries per 10,000 hours), gymnastics (68.18), rugby (59.77) and basketball (56.22). The rate of overuse injuries was high in swimming, badminton and athletics. The most common injuries was found to be common. The results of the study suggests that injury prevention programmes should be targeted to a wider range of sports, to females as well as to males, and that rehabilitation programmes need to be improved.

Sports injuries in the game of hurling. A one-year prospective study.

A prospective study of hurling injuries was conducted over the 8 months of one season on 74 players. These athletes averaged 4.30 +/- 2.58 hours per week of training and 1.15 +/- 0.21 hours per week of matches. Mean time of injury was 1.20 +/- 2.53 days in the hospital, 20.34 +/- 19.25 days off sport, and 13.34 +/- 17.25 days of restricted activity. Together this injury time amounts to 14.3% of the season. There were 92 match- and 43 training-related injuries, giving 342.47 injuries per 10,000 hours of matches and 43.83 injuries per 10,000 hours of training. Overall, there were 369.9 days of injury per 1000 hours of participation. The most common type of injury was muscle strain (24.4% of the 135 total injuries). The hamstrings was the most common site of strain, accounting for 41% of these injuries. Contusions comprised 16.3% of the injuries and sprains comprised 15.6%. The most frequently injured sites were the finger (13%), hamstrings (12%), back (11%), head (9%), and knee and ankle (9%). Forty-one percent of the injuries were attributed to foul play. The results of the study suggest that the incidence of injuries in hurling is high and may be attributed to poor conditioning, poor protection, and lack of enforcement of the rules.

Sports injuries in school gaelic football: a study over one season.

School football injuries were studied over the seven months of one season on 150 males aged 16.94 +/- 0.82 years. Training averaged 4.13 +/- 1.47 hours per week and matches 1.84 +/- 0.60 hours per week. Mean time injured was: 0.51 +/- 1.7 days in hospital, 34.27 +/- 37.08 days off sport and 13.98 +/- 5.22 days of restricted activity. There were 136 match and 63 training injuries giving 175.98 injuries per 10000 hours of matches and 31.06 injuries per 10000 hours of training. Injuries were treated as follows: hospital 83, general practitioners 51, physiotherapists 28, no treatment 38. The most common injuries were: ankle sprain (11.6% of the total), hamstring strain (6.5%), contusion (6.5%) back strain (6%) knee sprain (5.0%), finger sprain (5.0%), other muscle strains (5.0%), fracture of the wrist (5.0%), dislocation of the finger (4.5%), overuse injury of the back (4.0%), tenosynovitis (3.5%), fracture of the ankle (3.0%). Thirteen injuries were to goal-keepers, 85 to backs, 31 to mid-field players and 70 to forwards. In 34.83% of the injuries foul play was given as the major cause. This was followed by "Lack of fitness", "Poor kit or boots" and "Previous injury" (all 11.24%). The most common minor cause was "Poor state of the pitch" (17.42% of injuries).

Sports injuries in footballers related to defects of posture and body mechanics.

The objective of this study was to investigate possible relationships between the incidence of sports injury and the existence of body mechanics defects in players of various codes of football. Injuries were recorded prospectively over a 24 month period. Fifteen aspects of body mechanics were evaluated at the start of the study using a specially developed photogrammetric technique known to have high reliability and sensitivity. It was found that subjects who suffered from ankle injuries had lower mean scores for ankle mechanics than the non-injured players. Knee injuries were found to be associated with lumbar lordosis and sway back. Subjects who suffered from muscle strains had a higher incidence of lumbar lordosis, sway back and abnormal knee inter-space. Back injuries were associated with poor shoulder symmetry, scapulae abduction, back asymmetry, kyphosis, lordosis and scoliosis. Subjects who suffered from two or more injuries had lower overall body mechanics scores than the other subjects. In general, it was found that the incidence of ankle, back, knee and muscle injuries was influenced by the presence of defects of body mechanics. These results suggest that intervention to improve body mechanics would be likely to reduce the incidence of sports injuries in football.

Physical and fitness characteristics of successful Gaelic footballers.

Anthropometric and fitness observations were made on 32 members of a top level Gaelic football squad that reached the All Ireland final in the year in which these measurements were taken. The subjects were found to be large and well muscled with a mean somatotype of 2.6:5.6:3.1 (endomorphy:mesomorphy:ectomorphy). Body fat content of the whole squad averaged 15.0% but the most successful group of players averaged 12.4%. The body mass index (BMI) of the group was high and averaged 24.7 km.m-2. This group of Gaelic footballers was found to be taller and heavier than top level soccer players but smaller than Australian rules and American footballers. At 58.6 ml.min-1.kg-1 maximum oxygen uptake (VO2max) was higher than that reported for rugby players and American footballers and is probably similar to that of professional soccer players. Scores on three lung function tests: (1) forced vital capacity (FVC), (2) forced expiratory volume during 1 s (FEV1), and (3) peak expiratory flow rate (PEFR) were between 112% and 115% of the values predicted from height and age. There were wide variations in flexibility among the members of the group, the best individuals being as flexible as elite track and field athletes while the worst were less flexible than untrained subjects. Vertical jump scores were high and averaged 503 mm. The fitness observations made on this group of elite Gaelic footballers showed that they were not only fitter but more homogeneously fit than rugby players and American footballers and their fitness was generally similar to that reported for professional soccer players.

Flexibility and posture assessment in relation to hamstring injury.

Posture and flexibility were assessed in 34 athletes. Subjects were divided into two groups: (1) a noninjured group that did not have a history of hamstring strain injury within the previous 12 months; (2) an injured group that had a history of hamstring strain within the previous 12 months. Ten postural components were assessed: head erectness; shoulder symmetry; spinal curvature; hip symmetry; foot and ankle alignment; knee hyperextension; upper back roundness; trunk erectness; abdomen protrusion; and lumbar lordosis. Hamstring flexibility was assessed in both legs. Results indicated no difference (P > 0.05) in flexibility between groups (mean(s.d.) of both legs was: noninjured = 77.1(9.3) degrees, injured = 77.8(9.2) degrees. Also no difference (P > 0.05) was observed between the injured limb and the noninjured limb for injured subjects (injured limb = 78.1(11.1) degrees, noninjured limb = 77.5(8.1) degrees. A significant difference (P < 0.01) between groups occurred in low back posture (lumbar lordosis). No other difference occurred in the remaining nine posture components between groups. Intercorrelation coefficients among posture components indicated that at best only 53% of common variance existed between any two components (head and shoulder components: r = 0.73, P < 0.01). All other correlations indicated less than 40% common variance between components. The results of the study indicate that while differences in hamstring flexibility are not evident between injured and noninjured groups poorer low back posture was found in the injured group. Regular monitoring of posture in athletes is recommended.

Height, body weight, skinfold thickness and endurance fitness of children attending national schools in Ireland.

Height, body weight, the thickness of triceps, biceps, subscapular and supra-iliac skinfolds and the six-minute run-walk test of aerobic endurance were measured on 1163 National school children between the ages of 7 and 13, who were attending rural or urban schools in counties Cork, Galway, Limerick, Mayo, Waterford and Wexford. Height, weight and the sum of triceps and subscapular skinfolds were compared with 11 to 13 year-olds from Northern Ireland, for whom the same data is available. Endurance scores were compared with international norms. Although of the same height as other European children, the subjects were heavier and had higher skinfold thicknesses. Aerobic endurance scores averaged about 80% of international norms.

Incidence and nature of sports injuries in Ireland. Analysis of four types of sport.

The objectives of this study were to investigate the incidence of sports injuries in Ireland and to analyze various ways of quantifying the seriousness of these injuries. A 12-month, prospective study was carried out on 324 Irish athletes involved at a high level of sports participation in one of the following categories: endurance, contact, noncontact, or explosive sports. Results were expressed in four ways: 1) number of injuries per year; 2) days injured per year; 3) number of injuries per 10,000 hours of participation; and 4) duration of injury per 1000 hours of participation. The average athlete sustained 1.17 acute and 0.93 overuse injuries per year and suffered the effects of sports injury for 52 days. More time was lost through overuse injuries than acute injuries. The incidence of acute injuries per 10,000 hours of participation was lowest in the noncontact sports and highest in the contact sports, but there was no difference in the incidence of overuse injuries between any of the four categories of sport. The injury rate per 10,000 hours of participation was lowest in noncontact and explosive sports and highest in contact sports. However, when expressed in terms of days lost per 1000 hours of participation, endurance sports had the lowest incidence of time loss and explosive sports the highest.