Effects of pre-sleep protein consumption on muscle-related outcomes — A systematic review

ObjectivesThe timing of protein intake over the day on muscle mass and strength gains have received interest in the literature. Thus, the aim of this systematic review is to analyze clinical studies that evaluated the acute effects of pre-sleep protein consumption on overnight muscle protein synthesis and the chronic effects on muscle mass and strength.DesignsSystematic review.MethodsA literature search was conducted up to June 2020 according to PRISMA statement and nine articles were included to analyze.ResultsThe consumption of 20–40 g of casein approximately 30 min before sleep stimulates whole-body protein synthesis rates over a subsequent overnight period in young and elderly men (preceded or not by resistance exercise, respectively). In addition, pre-sleep protein consumption can augment the muscle adaptive response (muscle fiber cross-sectional area, strength and muscle mass) during 10–12 weeks of resistance exercise in young, but not in elderly men.ConclusionsBased on current evidence, the consumption of 20–40 g of casein approximately 30 min before sleep improves protein synthetic response during an overnight recovery period in healthy young adult men, with possible positive effects on muscle mass and strength following prolonged resistance exercise. In elderly, despite the initial evidence regarding the pre-sleep protein enhances overnight muscle protein synthesis rates, the current available evidence is limited precluding to conclude about the chronic effects on skeletal muscle mass or strength. These conclusions need to be taken with caution due to uneven protein intakes between experimental groups. Therefore, more data are needed before further considering pre-sleep protein as an effective nutritional intervention.     

Sex and occupation are salient factors associated with lateral ankle sprain risk in military tactical athletes

ObjectivesTo assess the risk of lateral ankle sprain (LAS) in male and female tactical athletes across different military occupations in the US military.DesignRetrospective cohort.MethodsThe Defense Medical Epidemiology Database was queried for the number of individuals with ICD-9 diagnosis codes 845.00 (sprain of ankle, unspecified) and 845.02 (calcaneofibular ligament sprain) on their initial encounter from 2006 to 2015. Relative risk (RR) and chi-square statistics were calculated assessing sex and occupational category on LAS risk.Results272,970 enlisted males (27.9 per 1000 person-years), 56,732 enlisted females (34.5 per 1000 person-years), 24,534 male officers (12.6 per 1000 person-years), and 6020 female officers (16.4 per 1000 person-years) incurred a LAS. Enlisted females in all occupational groups were at significantly higher risk for LAS than their male counterparts (RR 1.09–1.68; p < 0.001), except for Engineers (p = 0.15). Female officers had consistently higher risk for LAS in all occupational groups (RR 1.10–1.42; p < 0.001) compared with male officers, except Ground/Naval Gunfire (p = 0.23). Contrasted with Infantry, enlisted tactical athletes in the Special Operations Forces, Mechanized/Armor, Aviation, Maintenance, and Maritime/Naval Specialties were at lower risk (RR 0.38?0.93; p < 0.001), Artillery, Engineers, and Logistics Specialties were at higher risk (RR 1.04–1.18; p < 0.001), and Administration, Intelligence, and Communications were no different (p = 0.69). Compared with Ground/Naval Gunfire officers, Aviation officers were at significantly lower risk (RR, 0.75; p < 0.001), and Engineers, Maintenance, Administration, Operations/Intelligence, and Logistics officers were at higher risk (RR, 1.08–1.20; p < 0.001).ConclusionsSex and military occupation were salient factors associated with LAS risk.     

Are there really many runners out there? Is the proportion of runners increasing over time? A population-based 12-year repeated cross-sectional study with 625,460 Brazilians

ObjectivesTo investigate the proportion of individuals who practice running, its temporal trend, and to describe the runners’ characteristics.DesignPopulation-based repeated cross-sectional study.MethodsThe data from the Protective and Risk Factors for Chronic Diseases by Telephone Survey (Vigitel) from Brazil were used. Telephone interviews were conducted with adults from the Brazilian capitals (27 cities) between 2006–2017. The interviewer read the questions and recorded the participants’ responses immediately in a questionnaire. Data analyses were conducted using a Bayesian approach.ResultsThe Vigitel database consisted of 625,460 Brazilian participants composed of 295,681 exercisers and within them 15,529 runners. The mean yearly proportion of runners was about 2.45% (95% Bayesian credible interval [CrI] 1.93 to 3.11) and 5.32% (95%CrI 4.29 to 6.54) in the entire study population and within exercisers, respectively. The absolute increase in the proportion of runners per year over the 12-year period was 0.13% and 0.17% in the entire study population and within exercisers, respectively. Runners were more likely to be younger, men, within normal body mass index, highly educated, moderate alcohol drinkers, non-smokers, less exposed to TV, living near physical activity/sports facilities and less exposed to health conditions such as arterial hypertension, diabetes and dyslipidaemia.ConclusionThere was a 95% probability that the yearly proportion of runners lies between 1.93% and 3.11% in the population of the 27 Brazilian capitals, and between 4.29% and 6.54% within exercisers. There has been an increase in the proportion of runners over time. Runners were associated with healthier characteristics compared to non-runners and non-exercisers.     

Sports activity and patient-related outcomes after fixed-bearing lateral unicompartmental knee arthroplasty

BackgroundUnicompartmental osteoarthrosis increasingly affects younger patients who have high expectations concerning their postoperative level of activity. However, there is no available data on the activity level after fixed-bearing lateral unicompartmental knee arthroplasty (UKA). The aim of this study was to report sports activity after fixed-bearing lateral UKA with a minimum two-year follow up.MethodsNineteen patients were surveyed to determine their sporting activities at a mean follow up of 4.6 years (range 2.0–9.7 years) after fixed-bearing lateral UKA. We also assessed the Knee Injury and Osteoarthritis Outcome Score Joint Replacement (KOOS JR) Score and the University of California, Los Angeles activity scale (UCLA scale) at baseline and latest follow up.ResultsBefore the onset of the first symptoms, 15 of 19 patients were active in at least one sport compared with 13 of 19 patients after surgery. Eighty-six per cent of the patients returned to activity. Within 6 months, 68% returned to their activities after surgery. The mean postoperative UCLA score was 6.4 (±1.3). Half of the patients reached a high activity level (UCLA ≥ 7). Most common activities after surgery were long walks, biking and hiking. High-impact activities showed a significant decrease.ConclusionEighty-six per cent of the patients were able to return to regular recreational and sporting activities. In general, a shift from high-impact to low-impact activities was observed. There was no difference in the number of disciplines performed. Overall, the session length and frequency remained unchanged. However, male patients and younger patients participated in sports less frequently compared with preoperative levels.     

Effects of proprioceptive training on ankle muscle strength in fencers: A clinical trial

BackgroundFencing is a combat sport, which depends of lower limbs muscular strength and neuromuscular function. Because of that, approximately half of all injuries occur in lower limbs, especially in ankle. Thus, the objective of this study was to verify the influence of a twelve-week proprioceptive training program on ankle muscular strength and muscular balance in fencers.MethodsThe study was a clinical trial, with 19 fencing athletes from 14 to 35-year-old. The main outcome was ankle invertors, evertors, plantiflexors and dorsiflexors muscular strength and ankle muscle balance. The study was performed in six stages: familiarization of muscular strength test in isokinetic dynamometer; pre-intervention; intervention; post-intervention; three- and six-months follow-up. At pre-intervention stage, the muscular strength was evaluated. At intervention stage, the athletes performed 12-week proprioceptive training program, three times a week. At post-intervention, three- and the six-months follow-ups, same pre-intervention test was performed.ResultsThe proprioceptive training improved front leg ankle dorsiflexor strength at three- and six-months follow-ups compared to pre-intervention. Furthermore, training increased the front leg dorsiflexors/plantiflexors conventional ratio at three- and six-months follow-ups compared to pre-intervention; and evertors/invertors conventional ratio at three-months follow-up compared to pre-intervention; and evertors/invertors functional ratio at post-intervention and three- and six-months follow-ups compared to pre-intervention.ConclusionsThe improvement and/or maintenance of ankle muscle strength occurred in intervention group seems to be due to stimulus provided by proprioceptive training, with ankle dorsiflexors being the most stimulated group.     

Recovery profiles of eccentric hamstring strength in response to cooling and compression

IntroductionThe effectiveness of different forms of cryotherapy and combined compression (cryo-compression) commonly used in sport to enhance recovery following exercise are not fully understood. Therefore, the exploration of protocols that use contemporary cryo-compression is warranted. The purpose of the study was to investigate the effectiveness of using a cryo-compression device to recover hamstrings eccentric strength following a fatiguing exercise.MethodsEighteen healthy male adult footballers were randomly allocated to receive cryo-compression or rest following a lower limb fatiguing protocol. Cryo-compression was applied for 15-min, target temperature of 10 °C, and high intermittent pressure (5–75 mm Hg) using the Game Ready® device. Rest consisted of 15-min in a prone position on a plinth. To induce hamstring fatigue, participants performed the Yo-Yo intermittent fatigue test (IFT). Skin surface temperature (T_sk) and hamstring eccentric strength measures were taken at three time points; pre-IFT, immediately post-fatigue test (IPFT), and immediately post-intervention (IPI) (rest or Game Ready®). Participants returned one week later and performed the Yo-Yo IFT again and were exposed to the opposite intervention and data collection.ResultsSignificant decreases in T_sk over the posterior thigh were reported for all timepoints compared to pre cryo-compression temperatures (p=<0.05). Overall data displayed no significant main effects for timepoint or condition for PT or AvT (p=<0.05). There was no timepoint × condition interaction for PT or AvT (p=<0.05). Collapse of the data by condition (CC/R) demonstrated no significant effect for time for PT or AvT (p=>0.05).ConclusionsNo significant changes in HES occurred after exposure to cryo-compression or rest applied immediately following the Yo-Yo IFT. Further investigations to maximise beneficial application of contemporary cryo-compression applications in sport are required. Multiple measures of performance over rewarming periods, within competitive training schedules after sport-specific training are required to develop optimal cooling protocols for recovery.