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.

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.

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.

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.

The inclusion of vibration therapy in rehabilitating a gastrocnemius tear: a case study in master athlete.

[Purpose] The aim of this case study was to determine if VT could be included into a rehabilitation programme by monitoring the progress of muscle pain, range of motion and muscle strength. [Participant and Methods] An international male master hockey player sustained a medial gastrocnemius 5 cm tear prior to the World Cup. VT was applied early in the rehabilitation programme where 9 sessions of VT were performed during the first 16 days. Other conventional rehabilitative exercises were included. [Results] Twenty-eight days post-injury the athlete returned to full playing. Calf pain had subsided by day 8 with a change of 12° in ankle dorsi flexion range of motion. Grade 5 calf strength was attained by day 16, which was equivalent to the unaffected limb's strength. There were no residual side effects of including VT into the rehabilitation programme and it did not compromise the athlete's recovery. [Conclusion] To ensure optimal loading of VT, 9 sessions were implemented and progressively increased; consequently, there was no detrimental effect on the rehabilitative process. The athlete reported no side effects of using VT and its ease and time efficient application has a role to complementing soft tissue injury rehabilitation.

Evaluating gluteus maximus maximal voluntary isometric contractions for EMG normalization in male rugby players.

[Purpose] The aim of this study was to determine the highest electromyography (EMG) amplitude of the gluteus maximus from closed and open kinetic gluteal maximal voluntary isometric contractions (MVICs). [Participants and Methods] Ten healthy male rugby players performed three MVIC techniques that included, in random order: single leg squat, prone hip extension and standing gluteal squeeze. EMG signals were recorded from the inferior and superior regions of gluteus maximus of the dominant leg, and were normalized to the prone hip extension. [Results] For statistical analysis the EMG of both gluteus maximus regions were pooled together. The standing gluteal squeeze revealed a significantly lower EMG compared to single leg squat and prone hip extension. However, there was no significant difference in gluteal EMG activity between single leg squat and prone hip extension. [Conclusion] There is no distinct advantage for either single leg squat or prone hip extension in eliciting maximum EMG activity. Future research should compare the present positions with other MVICs that are commonly prescribed or have been demonstrated to produce high EMG amplitudes.

Evaluation of the temperature of posterior lower limbs skin during the whole body vibration measured by infrared thermography: Cross-sectional study analysis using linear mixed effect model.

BACKGROUND: Whole body vibration exercise (WBVE) has been shown to improve muscular strength and power, and increase peripheral blood flow. The aim of this study was to evaluate the behavior of the skin temperature (Tsk) on regions of the lower limbs from an acute bout of WBVE. METHODS AND FINDINGS: Cross-sectional study approved by local ethics committee (Certificado de Apresentação para Apreciação Ética-CAAE-19826413.8.0000.5259) and Trial registration (Registro Brasileiro de Ensaios Clínicos-REBEC-RBR-738wng). Using Infrared thermography (IRT), Tsk and thermal symmetry of the posterior lower extremities (thigh, knee, calf and heel) were examined in 19 healthy participants. IRT was assessed during 60-second WBVE exposures of 0, 30 and 50 Hz. From the adjusted linear mixed effects model, vibration frequency, time and regions of the lower extremity were significant (p<0.001). However, the variable laterality was not significant (p = 0.067) and was excluded from the adjusted statistical model. The adjusted model was significant (p<0.00001) and all variables in the model were significant (p<0.01) indicating that Tsk decreases with time, independently of the vibration frequency. The value of the Pseudo-R-Squared for the model was 0.8376. The presented mathematical model of the current study may be useful to justify the patterns observed for all vibration frequencies between and 0 and 50 Hz. The main limitations of the study were the reduced time of the intervention and not having evaluated other regions of the body. CONCLUSIONS: The acute exposure of 60-second mechanical vibration has effect on the behavior of Tsk of the posterior region of the lower limbs, which is likely to be associated with a decrease on the blood flow due to WBVE. It is speculated that during WBVE a greater supply of blood is required where the body responds by shunting blood flow from the skin to working muscle in the first seconds of exercise. Further investigative work is required to verify this hypothesis.

Active versus local vibration warm-up effects on knee extensors stiffness and neuromuscular performance of healthy young males.

OBJECTIVES: To compare the effects of local-vibration and active warm-up on knee extensors muscle stiffness and neuromuscular performance. DESIGN: Experimental crossover study. METHODS: Thirteen participants performed three 15-min warm-up protocols of control (CON), active (ACT) and local-vibration (LV) in separate testing session. Passive stiffness of vastus lateralis (VL) and vastus medialis (VM) by shear wave elastography and neuromuscular performance were assessed before and 2-min after each condition. RESULTS: A decrease in muscle stiffness was reported after ACT for VL (-16.0±6.6%; p<0.001) and VM (-10.2±8.7%; p=0.03) while no changes were reported after CON (p=0.46 and p=0.34 for VL and VM, respectively) and LV (p=0.07 and p=0.46 for VL and VM, respectively). Maximal jump performances increased during squat (+8.5±6.6%; p<0.001) and countermovement jump (+5.2±5.8%; p<0.001) after ACT while no changes were reported after CON and LV during squat (p=0.16 and p=0.81, respectively) and countermovement jump (p=0.18 and p=0.31, respectively). We further report that each condition was ineffective to inducing changes in maximal voluntary isometric contraction force (p=0.18), rate of force development (p=0.92), twitch parameters (p>0.05) as well as central modulations as reported by the unchanged voluntary activation level (p=0.24) and maximal electromyography (EMG) recorded from the VL (p=0.44). CONCLUSIONS: The active warm-up acutely reduced muscle stiffness and increased muscle performance during maximal dynamic tasks. With regard to LV, further studies are required to determine optimal parameters (frequency, amplitude, duration) to significantly increase muscle performance.

The acute effect of lower-limb warm-up on muscle performance.

It has been purported that the mechanism for muscular improvement after a gluteal warm-up protocol is likely to occur from neural activation. However, little is known about whether changes in muscular performance are due to changes in muscle activity. Therefore, the aim of this study was to determine whether a lower-limb warm-up that targets the gluteal muscle group would improve countermovement jump and short-distance sprinting through increased muscle activity. Ten semi-professional rugby union players (age 25.4 ± 2.9 yr; height 1.83 ± 6.7 m; body mass 96.8 ± 10.6 kg) with at least three years of resistance training experience volunteered for the study. In a cross-over design, participants performed countermovement jumps and 5 m sprints before and after a gluteal warm-up and a 10 min rest (control). Electromyography was used to measure muscle activity of the gluteus maximus and biceps femoris. Countermovement jump height significantly improved (7.9%, p < 0.05) after the lower-limb warm-up protocol compared with the control (3.2%). There was a significant (p < 0.05) improvement in sprint times over 2.5 m and 5 m regardless of the condition. There was no significant change in the muscle activity in any of the conditions. The results indicate that a lower-limb warm-up can acutely enhance countermovement jump performance compared to a control.

Cross transfer acute effects of foam rolling with vibration on ankle dorsiflexion range of motion.

INTRODUCTION: Foam roller is a device used as a massage intervention for rehabilitation and fitness performance. OBJECTIVE: To examine the effects on the ankle dorsiflexion mobility of the foam roller as well as the combination of foam roller and vibration applied to the ankle plantarflexors muscles, and to observe the possible cross-effect. METHODS: Thirty-eight undergraduate students participated in the study (19 males and 19 females). This study investigated. Three conditions (3 sets of 20 s) were performed in a randomized order (independent variables): 1) foam roller (Roller), 2) foam roller and vibration (Roller+VIB), and 3) no foam roller or vibration (Control). to determine whether of foam roller with or without vibration would benefit ankle dorsiflexion mobility. Ankle dorsiflexion ROM and plantar flexor were measured in both legs before and immediately after the treatment. RESULTS: A cross-effect was found in the non-stimulated leg. There was a significant effect on ankle mobility of Roller and Roller+VIB conditions (6% and 7%, p<0.001). CONCLUSION: Foam roller massage and vibration stimulus' foam roller massage increase ankle mobility producing a cross-effect.

Does short-term gluteal activation enhance muscle performance?

A reduction in gluteus maximus (GM) strength may contribute to the etiology of musculoskeletal impairments and lower-extremity injuries. Currently, there is a paucity of evidence regarding the efficacy of implementing a short-term gluteal activation programme to improving muscle performance. Twenty four semi-professional rugby males were assigned randomly to a gluteal activation group (GLUTE) or a control group (CON). During the 6-week training intervention, the GLUTE and CON groups performed the same training, however that GLUTE group performed seven gluteal activation exercises three times weekly prior to their normal training sessions. Whilst the CON group performed the conventional training with no gluteal activation exercises. Electromyography (EMG) was measured during a maximal isometric unilateral squat (MVIC) and unilateral hip extension force from the left and right vastus lateralis, gluteus maximus, and biceps femoris. After 6 weeks of training there was no significant main or interaction effect (p > 0.05) of EMG and peak force for MVIC and hip extension between GLUTE and CON. The current gluteal activation programme did not enhance EMG activity and hip extension force therefore, the body-weight exercises may not have been sufficient to elicit the appropriate changes.