Investigating scapula positioning in individuals with non-specific lower back pain: A preliminary study.

INTRODUCTION: Low back pain (LBP) is an economic and physically disabling burden on individuals and society. With 70% of cases classed as non-specific, there is a need for further research into the causes and consequences associated. The involvement of postural balance in musculoskeletal conditions is gaining increasing interest in research and health practice. However, there is a lack of literature surrounding LBP and posture in distal segments of the body. OBJECTIVE: The current study investigated scapula positioning in those with non-specific LBP. METHODS: Scapula angle of rotation, scapula protraction, and scapula elevation were assessed in nine participants with chronic non-specific LBP and compared with that of nine asymptomatic controls (aged 18-60 years). The degree of pelvic tilt was assessed across both groups as a secondary outcome measure. RESULTS: No difference was identified between the two sample groups for scapula angle of rotation (p = 0.707), protraction (p = 0.755), or elevation (p = 0.691). Anterior pelvic tilt was greater in those with LBP (p = 0.046), supporting previous literature. CONCLUSION: The findings for the scapula position are novel, given that research in this field is limited. It is concluded that there is no change in scapula positioning in those with non-specific LBP, but there is an increased anterior pelvic tilt.

Physiological Demands and Muscle Activity of "Track-Work" Riding in Apprentice Jockeys.

PURPOSE: To enhance performance in race riding, knowledge of current training workload is required. The objectives of this study were to quantify the physiological demands and profile the muscle activity of jockeys riding track-work. METHODS: Ten apprentice jockeys and 48 horses were instrumented with heart-rate monitors, accelerometers, and a surface electromyography BodySuit (recording 8 muscle groups: quadriceps, hamstrings, gluteal, lower back, obliques, abdominal, trapezial, and pectoral) that recorded continuously while riding their normal morning track-work. Data were extracted and time matched into 200-m sections for analysis once the jockey reached steady-state canter (6.9 m·s-1). RESULTS: Jockeys rode a mean (±SD) of 6 (1) horses each morning over 2.5 hours, spending ∼30 minutes at a canter (8.8 [ 0.7] m·s-1), with mean heart rate of 129 (11) beats·min-1 and ratings of perceived exertion representing easy-/moderate-intensity exercise. Mean magnitude of horse (0.17 [0.01] m) and jockey center of mass (0.16 [0.02] m) displacement per stride differed from that of the jockey's head (0.11 [0.01] m, P < .05). The majority of horse oscillation was damped in the upper body with a 3-fold reduction in the medio/lateral and fore/aft planes (P < .05), to minimize jockey head movement. Lower-body muscles absorbed horse motion, with core and upper-body muscles important for postural stabilization. CONCLUSIONS: The physiological demands of riding track-work were low, with no evidence of fatigue. Future research on jockeys in races as comparison would identify the specific requirements of a jockey-specific physical conditioning program.

Physiological Demands and Muscle Activity of Jockeys in Trial and Race Riding.

Physiological parameters and muscle activity of jockeys may affect their fall and injury risk, performance, and career longevity, as well as the performance and welfare of the horses they ride. Therefore, this study aimed to quantify the physiological demands, body displacement, and electromyographic (EMG) activity of twelve jockeys riding 52 trials and 16 professional races. The jockeys were instrumented with heart rate (HR) monitors, accelerometers, and integrated EMG clothing (recording eight muscle groups: quadriceps, hamstrings, gluteal, erector spinae/lower back, abdominal external obliques, abdominal, trapezial and pectoral) which recorded continuously whilst riding. During race day, jockeys rode an average of 5 ± 4 trials and 4 ± 2 races over 2−2.5 h. The trials represented lower intensity cardiovascular demand (~81% HRmax) and Training Impulse (TRIMP) scores (4.4 ± 1.8) than races at maximal intensity effort (~94% HRmax, 7.2 ± 1.8 TRIMP, p < 0.05). Jockey head displacement was similar in trials (5.4 ± 2.1 cm) and races (5.6 ± 2.2 cm, p > 0.05), with more vertical (6.7 ± 2.7 cm) and less medio/lateral (2.3 ± 0.7 cm) and fore/aft (3.7 ± 1.6 cm) displacement for jockeys riding in trials than races (5.5 ± 2.3, 2.8 ± 1.0, 5.6 ± 2.5 cm, p < 0.05). Jockeys in races adopted a lower crouched posture, with their centre of mass (COM) shifted anteriorly, using greater hamstring activation and less upper arm muscle activation than in trials. The differences in riding posture and physiological demands on jockeys riding in a race rather than a trial, highlight the requirement for an off-horse race-specific training programme to improve jockey fitness and performance. Greater jockey stability and coordination will have mutual benefits for both horse welfare and performance.

Strength and strength-related anthropometric parameters of the international level canoe slalom male paddlers / Fuerza y parámetros antropométricos relacionados con la fuerza de los hombres remeros de canotaje slalom de nivel internacional

SUMMARY: The aim of the study was to determine the differences in hand-grip strength and strength-related anthropometric parameters between the highest-performance international paddlers (HILP) and other international paddlers (ILP) in canoe slalom. In male competitors (n=48; 23 canoeists and 25 kayakers) who took part in the 2018 European championship event in canoe slalom in Prague, Czech Republic representing 15 European countries were measured hand-grip strength and strength-related anthropometric parameters two days prior the event. Differences between the group of HILP (medallists from Olympic Games, world championship and European championship in the previous three years and European championship finalists at the same time) and ILP were found. HILP have significantly higher forearm, arm and chest girths than ILP. Moderate or high practical differences and margin statistic differences were found also for hand-grip strength, body weight, body mass index and age. The consistently high-performing paddlers are heavier, have more muscular upper body and are stronger than the other group, while keeping their lower body lean. Therefore, regular upper-body strength training to all canoe slalom paddlers is important but caution is required because body weight over 80 kg may be a limiting factor.

RESUMEN: El objetivo del estudio fue determinar las diferencias en la fuerza de prensión manual y los parámetros antropométricos relacionados con la fuerza entre los remeros internacionales de alto rendimiento (RIAR) y otros remeros internacionales de canotaje en slalom. En hombres competidores (n=48; 23 piragüistas y 25 kayakistas) que participaron en el campeonato europeo de slalom en canoa de 2018, en Praga, República Checa, que representa a 15 países europeos, se midió la fuerza de agarre manual y los parámetros antropométricos relacionados con la fuerza dos días antes del evento. Se encontraron diferencias entre el grupo de RIAR (medallistas de Juegos Olímpicos, campeonatos del mundo y campeonatos de Europa en los tres años anteriores y finalistas del campeonato de Europa al mismo tiempo) y remeros internacionales. Los RIAR presentaban circunferencias de antebrazo, brazo y pecho significativamente más altas que los remeros internacionales. Además, se encontraron diferencias prácticas moderadas o altas y diferencias estadísticas en el límite para la fuerza de prensión manual, el peso corporal, el índice de masa corporal y la edad. Los remeros de alto rendimiento son más pesados, tienen la parte superior del cuerpo más musculosa y son más fuertes que el otro grupo, mientras mantienen la parte inferior del cuerpo esbelta. Por lo tanto, es importante el entrenamiento regular de fuerza de la parte superior del cuerpo para todos los remeros de piragüismo, sin embargo se requiere precaución debido a que el peso corporal superior a 80 kg puede ser un factor limitante.

Short-term effects of lumbopelvic complex stability training in elite female road cyclists.

OBJECTIVES: The purpose of this study was to determine the effects of short-term lumbopelvic stability training on muscular endurance and stability in elite female cyclists. METHODS: Twenty-four female road cyclists were randomly allocated to a core training group (CTG, n=12) or control group (CG, n=12). In addition to their scheduled training the CTG performed a core training program, that consisted of 6 core exercises performed in a session every other day until a total of 8 training sessions were completed. The CG did not receive the core training program and completed their scheduled training. The lumbopelvic-hip complex was assessed pre- and post-core program included the following exercises: single leg deadlift (SLD), bird-dog (BD), plank test (PT), and side-bridge plank test (SPT). RESULTS: In comparison to CG, CTG significantly improved the time to failure in PT, SPT-Left, and SPT-Right (p<0.05). Further, CTG resulted in a significant decrease in SLD (p<0.05) compared to CG for the three accelerometry measures. CONCLUSION: The present results indicate that following 8 sessions of lumbopelvic stability training muscular endurance and core stability were enhanced.

Acute Whole-Body Vibration Exercise Promotes Favorable Handgrip Neuromuscular Modifications in Rheumatoid Arthritis: A Cross-Over Randomized Clinical.

OBJECTIVE: Rheumatoid arthritis (RA) causes progressive changes in the musculoskeletal system compromising neuromuscular control especially in the hands. Whole-body vibration (WBV) could be an alternative for the rehabilitation in this population. This study investigated the immediate effect of WBV while in the modified push-up position on neural ratio (NR) in a single session during handgrip strength (HS) in women with stable RA. METHODS: Twenty-one women with RA (diagnosis of disease: ±8 years, erythrocyte sedimentation rate: ±24.8, age: 54± 11 years, BMI: 28 ± 4 kg·m-2) received three experimental interventions for five minutes in a randomized and balanced cross-over order: (1) control-seated with hands at rest, (2) sham-push-up position with hands on the vibration platform that remained disconnected, and (3) vibration-push-up position with hands on the vibration platform turned on (45 Hz, 2 mm, 159.73 m·s-2). At the baseline and immediately after the three experimental interventions, the HS, the electromyographic records (EMGrms), and range of motion (ROM) of the dominant hand were measured. The NR, i.e., the ratio between EMGrms of the flexor digitorum superficialis (FDS) muscle and HS, was also determined. The lower NR represented the greater neuromuscular efficiency (NE). RESULTS: The NR was similar at baseline in the three experimental interventions. Despite the nonsignificance of within-interventions (p = 0.0611) and interaction effect (p = 0.1907), WBV exercise reduced the NR compared with the sham and control (p = 0.0003, F = 8.86, η 2 = 0.85, power = 1.00). CONCLUSION: Acute WBV exercise under the hands promotes neuromuscular modifications during the handgrip of women with stable RA. Thus, acute WBV exercise may be used as a preparatory exercise for the rehabilitation of the hands in this population. This trial is registered with trial registration 2.544.850 (ReBEC-RBR-2n932c).

Preliminary Examination of the Biological and Industry Constraints on the Structure and Pattern of Thoroughbred Racing in New Zealand over Thirteen Seasons: 2005/06-2017/18.

This study aimed to examine thirteen seasons of flat racing starts (n = 388,964) in the context of an ecological system and identify metrics that describe the inherent characteristics and constraints of the New Zealand Thoroughbred racing industry. During the thirteen years examined, there was a 2-3% per year reduction in the number of races, starts and number of horses. There was a significant shift in the racing population with a greater number of fillies (aged 2-4 years) having a race start, and subsequent longer racing careers due to the inclusion of one more racing preparation post 2008 (p < 0.05). Additionally, there was an increasingly ageing population of racehorses. These changes resulted in more race starts in a career, but possibly because of biological constraints, there was no change in the number of race starts per season, starts per preparation, or days spelling between preparations (p < 0.05). There was no change in the proportion of horses having just one race start (14% of new entrants), indicating that the screening for suitability for a racing career remained consistent. These data identify key industry parameters which provide a basis for future modelling of intervention strategies to improve economic performance and reduce horse injury. Consideration of the racing industry as a bio-economic or ecological model provides framework to test how the industry may respond to intervention strategies and signal where changes in system dynamics may alter existing risk factors for injury.

Acute effect of whole-body vibration on electromechanical delay and vertical jump performance.

OBJECTIVES: To determine if a change in vertical jump performance from acute whole-body vibration can be explained by indirectly assessing spindle sensitivity from electromechanical delay. METHODS: Using a counter-balanced design, twenty college-aged participants performed whole-body vibration (WBV) and control treatments. WBV included 10 intervals (26 Hz, 3.6 mm) of 60 s in a half-squat followed by 60 s of rest. After 5 intervals, participants rested for 6-minutes before commencing the final 5 intervals. For the control, the exact same protocol of whole-body vibration was performed but without vibration. Electromechanical delay and vertical jump were assessed at baseline, during the 6-minute rest period and immediately after whole-body vibration and control. RESULTS: There were no differences between treatments, for both electromechanical delay (F(2, 38)=1.385, p=0.263) and vertical jump (F(2, 38)=0.040, p<0.96). Whole-body vibration had no effect on vertical jump performance. CONCLUSION: The current whole-body vibration protocol is not effective for acute vertical jump or electromechanical delay enhancement. Also, since there was no effect on electromechanical delay, this suggests that whole-body vibration did not enhance muscle spindle sensitivity for the parameters examined.

Effect of Resonant Frequency Vibration on Delayed Onset Muscle Soreness and Resulting Stiffness as Measured by Shear-Wave Elastography.

This study utilized resonant frequency vibration to the upper body to determine changes in pain, stiffness and isometric strength of the biceps brachii after eccentric damage. Thirty-one participants without recent resistance training were randomized into three groups: a Control (C) group and two eccentric exercise groups (No vibration (NV) and Vibration (V)). After muscle damage, participants in the V group received upper body vibration (UBV) therapy for 5 min on days 1-4. All participants completed a visual analog scale (VAS), maximum voluntary isometric contraction (MVIC), and shear wave elastography (SWE) of the bicep at baseline (pre-exercise), 24 h, 48 h, and 1-week post exercise. There was a significant difference between V and NV at 24 h for VAS (p = 0.0051), at 24 h and 1-week for MVIC (p = 0.0017 and p = 0.0016, respectively). There was a significant decrease in SWE for the V group from 24-48 h (p = 0.0003), while there was no significant change in the NV group (p = 0.9341). The use of UBV resonant vibration decreased MVIC decrement and reduced VAS pain ratings at 24 h post eccentric damage. SWE was strongly negatively correlated with MVIC and may function as a predictor of intrinsic muscle state in the time course of recovery of the biceps brachii.

Care planning, diagnosis and management in paediatric functional constipation.

Constipation is common in young children and results in approximately 350 hospitalisations per 100,000 population for 0-4-year-olds. Constipation can become chronic in more than one-third of those affected. The purpose of this article is to provide an awareness and highlight the care planning, diagnosis and management in paediatric functional constipation. It is intended for general practitioners and those in primary healthcare who may be unfamiliar with functional constipation. Paediatric functional constipation affects the child's physical, psychological and social wellbeing while causing significant stress to the caregiver/whanau. Despite its prevalence, functional constipation is often misdiagnosed and inadequately treated. Functional constipation requires a comprehensive therapeutic plan, including education, behavioural intervention and medication. Pharmacological treatment often causes concern and misapprehension for developing 'dependence', which is unfounded. Children with chronic constipation who do not progress, despite aggressive medical therapy and behavioural modification, may benefit from further assessment with colonic transit or anorectal and colonic manometry. In the future, novel medical, exercise and surgical strategies will have a role in advancing improved outcomes in children who are unresponsive to conventional medical and behavioural interventions. However, this will require more evidence-based guidelines. Unresponsive constipation cases should be included in the care planning of district health boards, which may assist in a multidisciplinary approach to assisting the physical and psychosocial aspects of constipation.

Morphological characteristics of European slalom canoe and kayak paddlers / Características morfológicas de los remeros de canoa y kayak de slalom europeos

SUMMARY: The primary aim of this study was to determine the morphology of elite canoe slalom paddlers and to identity if morphology differences existed between kayak and canoe paddlers. The survey included a total of 74 canoe slalom paddlers who competed in the 2018 European Championship. These competitors were assessed using a battery of anthropometric dimensions according to standardized anthropometric techniques and bioimpedance analysis using the multifrequency octopolar device Tanita MC-980. Elite slalom male competitors can be characterized to having average body height (~180 cm), average weight (~75 kg), with ectomorphic mesomorph somatotype (1.3 - 5.5 - 2.7), well developed trunk and arm muscles (biceps girth: 35.4 ± 1.8), low hypertrophy of legs and low body fat (8 ± 3.2 %). In addition, there are no significant differences between canoe (C1) and kayak (K1) paddlers. For female competitors we can conclude, there has been little change in anthropometric values through the decades. However, C1 competitors are younger, more mesomorphic and less ectomorphic.

RESUMEN: El objetivo de este estudio fue determinar la morfología de los remeros de canoa de slalom de élite e identificar si existían diferencias morfológicas entre los remeros de kayak y canoa. El análisis incluyó un total de 74 remeros de canoa slalom que compitieron en el Campeonato de Europa de 2018. Los competidores fueron evaluados mediante una batería de dimensiones antropométricas según técnicas antropométricas estandarizadas y análisis de bioimpedancia utilizando el dispositivo octopolar multifrecuencia Tanita MC-980. Los competidores masculinos de slalom de élite se pueden caracterizar por tener una estatura corporal promedio (~ 180 cm), un peso promedio (~ 75 kg), con somatotipo mesomorfo ectomorfo (1,3 - 5,5 - 2,7), músculos del tronco y del brazo bien desarrollados (circunferencia del bíceps: 35,4 ± 1,8), baja hipertrofia de piernas y baja grasa corporal (8 ± 3,2 %). Además, no existen diferencias significativas entre los remeros en canoa (C1) y kayak (K1). Para las competidoras, podemos concluir que se han observado pocos cambios en los valores antropométricos a lo largo de las décadas. Sin embargo, los competidores de C1 son más jóvenes, más mesomórficos y menos ectomórficos.

The effects of whole-body vibration on EMG activity of the lower body muscles in supine static bridge position.

OBJECTIVES: The purpose of the current study was to firstly examine the effects of different whole-body vibration (WBV) frequencies in the lower-body muscles when applied simultaneously during a bridge exercise. Secondly, determine if there were any sex differences in the lower-body muscles of WBV during the bridge. METHODS: Seven females and 7 males completed 2 familiarization and 1 test sessions. In the test session participants were randomized to complete one 30 s bout of a bridge exercise for 3 separate conditions followed by 3-min of rest. The 3 conditions (a) No-WBV (without WBV); (b) WBV-30 (30 Hz, low amplitude); (c) WBV-50 (50 Hz, low amplitude) were performed on a WBV platform. Muscle activity of the biceps femoris (BF), semitendinosus (ST), gluteus maximus (Gmax), multifidus muscle (MF) muscles were measured. RESULTS: Muscle activity was increased with WBV in the BF and ST muscles at WBV-30 and WBV-50 conditions (p<0.05) vs. no-WBV. During No-WBV and WBV-50 conditions, males had a higher biceps femoris activity compared to females for (p<0.05) 45 and 27 %, respectively; however, during all conditions females had a high level of Gmax activity (57%) than males (p<0.05). CONCLUSION: Additional vibration at 30 and 50 Hz during the bridge exercise could be a useful method to enhance hamstring muscle activity.

Using Sprint Velocity Decrement to Enhance Acute Sprint Performance.

ABSTRACT: Cochrane, DJ and Monaghan, D. Using sprint velocity decrement to enhance acute sprint performance. J Strength Cond Res 35(2): 442-448, 2021-Acute sled towing has the capability to elicit a potentiation. Currently, sled loading is determined from body mass (BM) percent. However, it may be more relevant to use a percentage of maximal sprint reduction to determine an individual's load. The purpose of this study was to determine if individualizing sled loads at 35 and 55% reduction in velocity would improve 20-m sprint performance. In addition, electromyography (EMG) was assessed to determine if any sprint-related improvements in velocity were due to changes in neural excitation. Twelve senior club male rugby union players performed familiarization and 2 sled towing sessions using a randomized, cross-over, and counterbalanced design. Testing sessions involved: baseline unresisted 20-m sprints, resisted sprint (35 and 55% reduction in velocity), and unresisted 20-m sprints at 2, 4, 6, 8, 12, and 16 minutes. The sled load to reduce maximal velocity by 35% significantly improved 20-m velocity (p <0.05, effect size [ES] = 0.21) compared with the heavier sled load (55% reduction in maximum velocity). A significant decline in sprint velocity occurred at 12 minutes (p < 0.01, ES = -0.61) and 16 minutes (p < 0.01, ES = -0.45) compared with baseline velocity. Other time intervals reported trivial small nonsignificant changes in sprint velocity (p >0.05). There was no significant change in EMG. Reducing sprint velocity provides an alternate method to determining sprint loading. Nonetheless, a greater range of reduced sprint velocity is required to assess if it is more effective than using BM percent procedure.

Peak Power Output and Onset of Muscle Activation During High Pull Exercise.

ABSTRACT: Barnes, MJ, Petterson, A, and Cochrane, DJ. Peak power output and onset of muscle activation during high pull exercise. J Strength Cond Res 35(3): 675-679, 2021-The aim of this study was to determine the percentage of 1 repetition maximum (1RM) at which peak power output occurred during the high pull (HP) exercise. In addition, the onset time of the biceps femoris (BF) and gluteus maximus (GM), across a range of loads, was investigated. Twelve resistance-trained men performed 1RM testing for the HP followed by lifts at 10% increments from 30 to 80% 1RM. During each load of power, output was measured using a linear potentiometer, whereas surface electromyography was recorded from the BF and GM. Peak power output occurred at 70% (1881.9 ± 296.1 W); however, there was no significant difference between loads at 60-80% (all p > 0.05). Loads between 40 and 80% 1RM produced significantly higher power outputs than 30% while 80% generated greater power than 100% 1RM (all p < 0.05). There was no significant (p > 0.05) main effect of muscle or load in the onset of BF (156.5-212.1 ms) or GM (112.1-158.1 ms). Therefore, these results suggest that training at a load between 60 and 80% 1RM may be useful in increasing power in the HP. In addition, activation of 2 of the hip extensors occurs in a relatively synchronous order irrespective of load.

Individual Responses to Different Vibration Frequencies Identified by Electromyography and Dynamometry in Different Types of Vibration Application.

ABSTRACT: Oliveira, MP, Menzel, H-JK, Cochrane, DJ, Drummond, MD, Demicheli, C, Lage, G, and Couto, BP. Individual responses to different vibration frequencies identified by electromyography and dynamometry in different types of vibration application. J Strength Cond Res 35(6): 1748-1759, 2021-The application of mechanical vibration is a common neuromuscular training technique used in sports training programs to generate acute increases in muscle strength. The principal aim of the study was to compare the individual optimal vibration frequency (IOVF) identified by electromyography (EMG) activity and force production in strength training. Twenty well-trained male volunteers (age: 23.8 ± 3.3 years) performed a familiarization and 2 interventions sessions, which included 5 maximal voluntary contractions (MVCs) of the elbow flexors with a duration of 10 seconds and 5-minute intervals between each MVC. The first MVC was performed without vibration followed by 4 randomized MVCs with application of vibration in the direction of the resultant muscle forces' vector (VDF) or whole-body vibration (WBV) at frequencies of 10, 20, 30, or 40 Hz. The mechanical vibration stimulus was superimposed during the MVC. Individual optimal vibration frequency, as identified by EMG, did not coincide with IOVF identified by force production; low agreement was observed between the vibration frequencies in generating the higher EMG activity, maximal force, and root mean square of force. These findings suggest that the magnitude of the vibratory stimulus response is individualized. Therefore, if the aim is to use acute vibration in conjunction with strength training, a preliminary vibration exposure should be conducted to determine the individualized vibratory stimulus of the subject, so that training effects can be optimized.

Cross-Sectional Survey of the Training Practices of Racing Greyhounds in New Zealand.

The aim of this study was to conduct a cross-sectional survey of racing greyhound trainers in New Zealand in order to provide an overview of their training practices. A survey regarding training practices was posted to all registered greyhound training license holders in New Zealand in August 2019. Data were collected from a convenience sample of 48 trainers (35.6%; n = 48/137) who completed the survey. Other than the differences in the number of greyhounds in race training, the training programmes described by public trainers and owner trainers were similar. Trainers reported that the primary reason for registering young dogs for racing and for qualifying for racing was the ability to meet time milestones. Young dogs had a median of six (interquartile range (IQR): 4-10) trials before they commenced their racing career. Trainers described training practices that aimed to prepare greyhounds for race-day. Regardless of whether the dogs raced once or twice a week, most training programmes demonstrated high specificity where training involved two periods of load cycles through high-intensity workload. Trainers racing their greyhounds once a week simulated the workload of trainers racing their greyhounds twice a week by introducing one high-intensity (speed) workout during the week. Training programmes were structured to condition the dogs to the physiological and metabolic requirements of sprint racing. This study highlights the importance of the need for an improved understanding of training and competition load in order to enable future research in the field of racing greyhounds.

Incidence and risk factors for race-day jockey falls over fourteen years.

OBJECTIVES: To determine the incidence of, and risk factors for, race-day jockey falls occurring in Thoroughbred flat and jumps (hurdle and steeplechase) racing. DESIGN: Retrospective cohort study. METHODS: Incidence rates for race-day jockey falls over 14 racing seasons in New Zealand (n=421,596 race-day starts) were calculated per 1000 rides. Univariable and multivariable analyses of jockey, horse and race level risk factors were conducted with Poisson regression in a generalized linear mixed model. RESULTS: Most races (97%, n=407,948 race starts) were flat racing with 10 races/race-day, whilst most jumps races were longer and had 2 races/race-day. The rate of jockey falls was higher in steeplechase racing (99.9/1000, 95% CI 92.2-108.4) than hurdle (53.2/1000, 95% CI 48.7-58.3) and flat racing (1.2/1000, 95% CI 1.1-1.3, p<0.001). Experienced athletes (both horse and jockey) had lower IRR. In flat racing, IRR increased linearly with the number of race-day rides by the jockey. In jumps races, IRR increased with a fall in a previous race (IRR 1.5/1000, 95% CI 1.3-1.7, p<0.001). A shorter jumps race distance reduced the IRR of a jockey fall. CONCLUSIONS: Athlete experience was associated with risk of jockey falls. The linearity of race ride number with IRR and longer distance in jumps racing, indicated that cognitive or physiological fatigue may play a role in the risk of a race-day fall. This data highlights the role sport-specific conditioning programmes may have on reducing risk.

Potential Application of Whole Body Vibration Exercise For Improving The Clinical Conditions of COVID-19 Infected Individuals: A Narrative Review From the World Association of Vibration Exercise Experts (WAVex) Panel.

COVID-19 is a highly infectious respiratory disease which leads to several clinical conditions related to the dysfunction of the respiratory system along with other physical and psychological complaints. Severely affected patients are referred to intensive care units (ICUs), limiting their possibilities for physical exercise. Whole body vibration (WBV) exercise is a non-invasive, physical therapy, that has been suggested as part of the procedures involved with pulmonary rehabilitation, even in ICU settings. Therefore, in the current review, the World Association of Vibration Exercise Experts (WAVEX) reviewed the potential of WBV exercise as a useful and safe intervention for the management of infected individuals with COVID-19 by mitigating the inactivity-related declines in physical condition and reducing the time in ICU. Recommendations regarding the reduction of fatigue and the risk of dyspnea, the improvement of the inflammatory and redox status favoring cellular homeostasis and the overall improvement in the quality of life are provided. Finally, practical applications for the use of this paradigm leading to a better prognosis in bed bound and ICU-bound subjects is proposed.

Can Backward Sled Towing Potentiate Sprint Performance?

Monaghan, DJ and Cochrane, DJ. Can backward sled towing potentiate sprint performance? J Strength Cond Res 34(2): 345-354, 2020-The objectives of this study were to determine whether backward sled towing can elicit a postactivation potentiation response to enhance forward 5-m sprint performance and to determine whether sled loading through a reduction in velocity can elicit an improvement in 5-m sprint performance. A randomized design was used to examine the effects of forward and backward sled tow loading of 35 and 55% reduction of individual's maximal velocity (rVelmean) on 5-m sprint performance. Eighteen well-trained male subjects performed 4 intervention sessions (55% rVelmean backward; 55% rVelmean forward; 35% rVelmean backward; and 35% rVelmean forward) separated by a minimum of 24 hours. Intervention sessions included baseline unresisted 5-m sprints, followed by 3 loaded sled tows over a distance of 3.2 m or 5 m for heavy and light loads, respectively. An unresisted 5-m sprint was completed after 6 and 12 minutes of rest. Mean sprint velocity, electromyography, sprint kinematic, and temporal data were collected during each session. Sled towing, irrespective of load or rest period, produced no significant change in 5-m sprint velocity (p > 0.05). In addition, there were no significant changes in electromyography, kinetic, and temporal data; however, current findings support previous research of confirming muscle activation and vertical force production during sprint acceleration. It is unclear whether individualizing a reduction in velocity is a superior method to percent body mass for optimizing sled loading in well-trained male subjects.

An exploratory study of vibration therapy on muscle function in patients with peripheral artery disease.

OBJECTIVE: The purpose of this exploratory study was to determine whether a single session of vibration therapy (VT) would improve muscular and functional performance in individuals with symptomatic peripheral artery disease (PAD). METHODS: In a randomized, balanced cross-over design fourteen PAD participants with intermittent claudication (mean ± standard deviation; age, 73.9 ± 4.6 years; height, 172.6 ± 68.4 cm; body mass, 85.2 ± 15.7 kg) performed VT and control that involved repeated chair rises, timed up-and-go test, and 6-minute walk test. Each intervention was separated by at least 2 days. Wearable VT devices were positioned on the right and left lower limbs that were turned on during functional testing but were turned off for the control intervention. RESULTS: VT significantly improved (P < .05) repeated chair rises and timed up-and-go test compared with control with a small effect size of 0.46 and 0.45, respectively. Similarly, a significant (P < .01) and meaningful change in 6-minute walk test was noted in VT compared with control. CONCLUSIONS: This exploratory study suggest that VT may enhance functional strength, mobility, and walking performance by extending the onset of claudication and increasing walking distance in PAD with intermittent claudication. However, further study is required to confirm and extend these preliminary findings and determine the potential mechanisms of action in VT.