Quantifying the injury of the human eye components due to tennis ball impact using a computational fluid–structure interaction model

Although it might be believed that the eye only comprised a very small area of the face, its injury due to the ball impacts in different sports seems to be severe enough to entice many researchers to determine the level of injury and then attempt to minimize it. Sports-related eye injuries, especially tennis, pose a substantial and preventable problem to the eye due to the high speed of the tennis ball (69 m/s). This is why many ophthalmologists provide a wide range of information for their patients regarding the risks of eye injuries in tennis to prevent the injury to well over 100,000 eyes each year. However, so far although there are some general information regarding the injury to the human eye components due to the tennis ball impact, the details of the stresses and deformations have not been well determined. Therefore, the goal of this study was to determine the stresses and deformations of the eye components, including cornea, aqueous body, iris, ciliary body, lens, vitreous body, retina, sclera, optic nerve, extra and intraconal fats, and muscles, attributable to the tennis ball impact via a Lagrangian–Eulerian computational coupling model. Magnetic resonance imaging was employed to establish a finite element model of the human eye according to a normal human eye. The numerical results revealed the highest amount of stress in the iris (19.2 MPa), whereas the lowest one was observed in the vitreous body (1.77 Pa). The cornea also experienced the stress of 8.27 MPa which might be high enough to invoke rupture in this delicate material. In addition, the results exhibited a decreasing and increasing of the radius of curvature for the cornea and lens, respectively. Finally, the collision of the tennis ball to the eye triggered the resultant displacement of 0.045 µm in the optic nerve which may imply a non-significant injury to that. The findings of this study may have implications not only for understating the values of stresses and deformations in the human eye components but also for helping the ophthalmologists to have a more precise diagnosis about the injury position in the eye due to the tennis ball impact.     

The effects of a 4-week static stretching programme on the individual muscles comprising the hamstrings

The aims of this study were to investigate the effects of a 4-week intervention of static stretching (SS) on muscle hardness of the semitendinosus (ST), semimembranosus (SM) and biceps femoris (BF) muscles. Shear elastic modulus was measured by using ultrasound shear wave elastography as the index of muscle hardness. Thirty healthy men (age 22.7 ± 2.2 years) volunteered for this study and were randomly assigned to the SS intervention group (n = 15) or the control group (n = 15). Participants in the SS intervention group received a 4-week stretch intervention for the hamstrings of their dominant leg. Shear elastic moduli of the hamstrings were measured at initial evaluation and after 4 weeks in both groups at a determined angle. In all muscles, the shear elastic modulus decreased significantly after SS intervention. The percentage change in the shear elastic modulus from the value at initial evaluation to after 4 weeks intervention was greatest in the SM. These results suggest that SS intervention has chronic effects on reducing hardness of the hamstring muscle components, especially the SM muscle.     

Landing ground reaction forces in figure skaters and non-skaters

Abstract

Researchers and clinicians have suggested that overuse injuries to the lower back and lower extremities of figure skaters may be associated with the repeated high impact forces sustained during jump landings. Our primary aim was to compare the vertical ground reaction forces (GRFs) in freestyle figure skaters (n = 26) and non-skaters (n = 18) for the same barefoot single leg landing on a force plate from a 20 cm platform. Compared with non-skaters, skaters exhibited a significantly greater normalised peak GRF (3.50 ± 0.47 × body weight for skaters vs. 3.13 ± 0.45 × body weight for non-skaters), significantly shorter time to peak GRF (81.21 ± 14.01 ms for skaters vs. 93.81 ± 16.49 ms for non-skaters), and significantly longer time to stabilisation (TTS) of the GRF (2.38 ± 0.07 s for skaters vs. 2.22 ± 0.07 s for non-skaters). Skaters also confined their centre of pressure (CoP) to a significantly smaller mediolateral (M–L) (25%) and anterior–posterior (A–P) (40%) range during the landing phase, with the position of the CoP located in the mid to forefoot region. The narrower and more forward position of the CoP in skaters may at least partially explain the greater peak GRF, shorter time to peak, and longer TTS. Training and/or equipment modification serve as potential targets to decrease peak GRF by distributing it over a longer time period. More comprehensive studies including electromyography and motion capture are needed to fully characterise the unique figure skater landing strategy.     

Predicting the throwing velocity of the ball in handball with anthropometric variables and isotonic tests

Abstract

The aims of this study were to (1) investigate the influence of general anthropometric variables, handball-specific anthropometric variables, and upper-limb power and strength on ball-throwing velocity in a standing position (ν_ball), and (2) predict this velocity using multiple regression methods. Forty-two skilled male handball players (age 21.0 ± 3.0 years; height = 1.81 ± 0.07 m; body mass = 78.3 ± 11.3 kg) participated in the study. We measured general anthropometric variables (height, body mass, lean mass, body mass index) and handball-specific anthropometric parameters (hand size, arm span). Upper-limb dynamic strength was assessed using a medicine ball (2 kg) throwing test, and power using a one-repetition maximum bench-press test. All the variables studied were correlated with ball velocity. Medicine ball throwing performance was the best predictor (r = 0.80). General anthropometric variables were better predictors (r = 0.55–0.70) than handball-specific anthropometric variables (r = 0.35–0.51). The best multiple regression model accounted for 74% of the total variance and included body mass, medicine ball throwing performance, and power output in the 20-kg bench press. The equation formulated could help trainers, athletes, and professionals detect future talent and test athletes' current fitness.     

Influence of wheel size on muscle activity and tri-axial accelerations during cross-country mountain biking

ABSTRACT

This study aimed to investigate the influence of different mountain bike wheel diameters on muscle activity and whether larger diameter wheels attenuate muscle vibrations during cross-country riding. Nine male competitive mountain bikers (age 34.7 ± 10.7 years; stature 177.7 ± 5.6 cm; body mass 73.2 ± 8.6 kg) participated in the study. Riders performed one lap at race pace on 26, 27.5 and 29 inch wheeled mountain bikes. sEMG and acceleration (RMS) were recorded for the full lap and during ascent and descent phases at the gastrocnemius, vastus lateralis, biceps brachii and triceps brachii. No significant main effects were found by wheel size for each of the four muscle groups for sEMG or acceleration during the full lap and for ascent and descent (P > .05). When data were analysed between muscle groups, significant differences were found between biceps brachii and triceps brachii (P < .05) for all wheel sizes and all phases of the lap with the exception of for the 26 inch wheel during the descent. Findings suggest wheel diameter has no influence on muscle activity and vibration during mountain biking. However, more activity was observed in the biceps brachii during 26 inch wheel descending. This is possibly due to an increased need to manoeuvre the front wheel over obstacles.     

Injuries in football (soccer)—a systematic review of epidemiology and aetiological aspects

Increasing injury incidences prove the importance of injury prevention in football. The aim of this review was to summarise the recent evidence on the epidemiology and inciting events of acute injuries within subgroups (performance level, age and sex). A systematic literature search was conducted in the databases PubMed, CINAHL, Embase, Cochrane, PEDro, and SPORTDiscus for articles published from 1 January 2014 until 15 October 2017. The search yielded 4690 results. After the initial screening of titles and abstracts, 182 studies underwent detailed full-text screening according to the inclusion and exclusion criteria. Finally, 53 studies were included. Of these, 46 papers contained epidemiological data, with a total of approximately 41,212 observed player seasons and 11 further tournaments, including 7122.5 observed matches with approximately 126,748.5 player hours. A total of 30,844 injuries were identified. The overall injury incidence ranged from 0.6 to 20.3 injuries per 1000?h of exposure. The locations at highest risk of injury were the lower limbs, particularly the thighs, knees and ankles. Injury-inciting events were reported in 12 studies, involving a total of 8035 injuries. Of these 12 studies, 5 considered all body locations, 3 concentrated on anterior cruciate ligament injuries, 1 reported on general head injuries, 2 reported on concussions, and 1 reported on midfacial trauma only. One of the main findings of this review was that playing football does not necessarily imply a high risk of injury. Promising preventive approaches are being used to revise implementation strategies of evident training programmes and management of individual workloads.     

The influence of pitch dimensions on performance during small-sided and conditioned soccer games

Abstract

This study examined the influence of pitch dimensions in small-sided soccer games in shaping opportunities for performers to maintain ball possession, pass to teammates and shoot at goal. Fifteen amateur standard male participants (M = 21.87, σ = 1.96 years) played 5 v 5 small-sided soccer games in three varying pitch conditions (28 m × 14 m, 40 m × 20 m and 52 m × 26 m). Thirty sequences of play in each condition were selected for digitisation using TACTO software, allowing the capture of bi-dimensional displacement coordinate data of all players and the ball. The values of interpersonal distance between all attackers and immediate defenders and the relative distances of defenders to intercept a shot and a pass were computed as dependent variables. Results showed existence of fewer opportunities to maintain ball possession on smaller pitches, compared to medium and larger pitches. Conversely, the different dimensions set to the pitch did not influence opportunities for players to shoot at goal, or to perform passes to other teammates. By examining the specific spatial–temporal relationships of players and key-task constraints, the data from this study explain how effects of manipulating pitch dimensions of small-sided games might enhance opportunities for acquiring specific movement and decision-making skills.     

The use of spatial manipulation to examine goalkeepers’ anticipation

This study investigated whether anticipation and search strategies of goalkeepers are influenced by temporally and spatially manipulated video of a penalty. Participants were clustered into three groups depending on skill: goalkeepers (n = 17), field players (n = 20) and control group (n = 20). An eye tracker was worn whilst watching 40 videos of a striker kicking to four corners of a goal in random order. All 40 videos were temporally occluded at foot-to-ball contact, and the non-kicking leg of 20 videos was spatially manipulated. Results showed that goalkeepers had significantly better predictions than the two groups with no differences between the two testing conditions. According to effect size, the percentage of fixation location and viewing time of the kicking leg and ball were greater for the goalkeepers and field players group than the control group irrespective of testing conditions. The fixations on the kicking leg and ball in conjunction with comparable predictions between spatially manipulated and control conditions suggest that goalkeepers may not rely on the non-kicking leg. Furthermore, goalkeepers appear to use a global perceptual approach by anchoring on a distal fixation point/s of the penalty taker whilst using peripheral vision to obtain additional information.     

The effect of mountain bike wheel size on cross-country performance

ABSTRACT

The purpose of this study was to determine the influence of different wheel size diameters on indicators of cross-country mountain bike time trial performance. Nine competitive male mountain bikers (age 34.7 ± 10.7 years; stature 177.7 ± 5.6 cm; body mass 73.2 ± 8.6 kg) performed 1 lap of a 3.48 km mountain bike (MTB) course as fast as possible on 26″, 27.5″ and 29″ wheeled MTB. Time (s), mean power (W), cadence (revs · min^?1) and velocity (km · h^?1) were recorded for the whole lap and during ascent and descent sections. One-way repeated measure ANOVA was used to determine significant differences. Results revealed no significant main effects for any variables by wheel size during all trials, with the exception of cadence during the descent (F_{(2, 16)} = 8.96; P = .002; P² = .53). Post hoc comparisons revealed differences lay between the 26″ and 29″ wheels (P = .02). The findings indicate that wheel size does not significantly influence performance during cross-country when ridden by trained mountain bikers, and that wheel choice is likely due to personal choice or sponsorship commitments.     

Does ball carrier technique influence tackler head injury assessment risk in elite rugby union?

The aim of this study was to use video evidence of tackles in elite level rugby union to identify ball carrier proficiency characteristics, for both lower and upper body tackles, that have a higher propensity to result in Head Injury Assessments(HIA) for the tackler. HIA (n = 74) and non-HIA tackles (n = 233) were categorised as either front-on or side-on upper or lower body tackles and scored for ball carrying proficiency characteristics. Side-on tackles included tackles from behind. A Chi-Square test (p < 0.05) and Cramer’s V were calculated to compare proficiency characteristics in HIA and non-HIA cases. For front-on upper body tackles, the ball carrier “fending into contact” (p < 0.01;ES = Moderate) and “explosiveness on contact” (p = 0.04;ES = Moderate) had a higher propensity to result in a HIA for the tackler. Fending into contact was exhibited in 47% of all upper body Tackle front-on HIA cases. The fending arm contacted the tackler’s head in 67% of these cases. Fending into contact can potentially be dangerous and therefore emphasis should be placed on safe fending during tackle-based training drills. Referees should also be alert to arm-to-head contact during the fend. Given the low number of ball carrier characteristics identified, focus should be placed on tackler characteristics for HIA prevention strategies.     

Sprint kayaking and canoeing performance prediction based on the relationship between maturity status,anthropometry and physical fitness in young elite paddlers

This study aimed to identify the maturity-related differences and its influence on the physical fitness, morphological and performance characteristics of young elite paddlers. In total, 89 kayakers and 82 canoeists, aged 13.69 ± 0.57 years (mean ± s), were allocated in three groups depending on their age relative to the age at peak height velocity (pre-APHV, circum-APHV and post-APHV) and discipline (kayak and canoe). Nine anthropometric variables, a battery of four physical fitness tests (overhead medicine ball throw, countermovement jump, sit-and-reach test and 20 m multistage shuttle run test) and three specific performance tests (1000, 500 and 200 m) were assessed. Both disciplines presented significant maturity-based differences in all anthropometric parameters (except for fat and muscle mass percentage), overhead medicine ball throw and all performance times (pre > circum > post; P < 0.05). Negative and significant correlations (P < 0.01) were detected between performance times, chronological age and anthropometry (body mass, height, sitting height and maturity status), overhead medicine ball throw and sit and reach for all distances. These findings confirm the importance of maturity status in sprint kayaking and canoeing since the more mature paddlers were also those who revealed largest body size, physical fitness level and best paddling performance. Additionally, the most important variables predicting performance times in kayaking and canoeing were maturity status and chronological age, respectively.     

The influence of cricket fast bowlers’ front leg technique on peak ground reaction forces

Abstract

High ground reaction forces during the front foot contact phase of the bowling action are believed to be a major contributor to the high prevalence of lumbar stress fractures in fast bowlers. This study aimed to investigate the influence of front leg technique on peak ground reaction forces during the delivery stride. Three-dimensional kinematic data and ground reaction forces during the front foot contact phase were captured for 20 elite male fast bowlers. Eight kinematic parameters were determined for each performance, describing run-up speed and front leg technique, in addition to peak force and time to peak force in the vertical and horizontal directions. There were substantial variations between bowlers in both peak forces (vertical 6.7 ± 1.4 body weights; horizontal (braking) 4.5 ± 0.8 body weights) and times to peak force (vertical 0.03 ± 0.01 s; horizontal 0.03 ± 0.01 s). These differences were found to be linked to the orientation of the front leg at the instant of front foot contact. In particular, a larger plant angle and a heel strike technique were associated with lower peak forces and longer times to peak force during the front foot contact phase, which may help reduce the likelihood of lower back injuries.     

Improvement of cellular health indicators and muscle quality in older women with different resistance training volumes

ABSTRACT

The main purpose of this study was to compare the effects of resistance training (RT) performed with different training volumes on phase angle (PhA), body water components, and muscle quality (MQ) in untrained older adult women. A second purpose was to assess the relationship between PhA and MQ. Sixty-two older adult women (68.6 ± 5.0 years, 65.2 ± 13.3 kg, 156.1 ± 6.2 cm) were randomly assigned into one of the three groups: two training groups performed either 1 set (G1S) or 3 sets (G3S), or a control group (CG). Body water components and PhA were estimated by bioelectrical impedance (BIA). MQ was determined by dividing skeletal muscle mass estimated by dual-energy absorptiometry (DXA) by total muscle strength from three exercises. After the intervention period, both training groups demonstrated improvements (P < 0.05) when compared with CON for intracellular water, total body water, PhA, and MQ. These results suggest that RT can improve PhA, body water components, and MQ after 12 weeks of RT in untrained older women, regardless of training volume. Furthermore, changes in MQ were positively correlated with changes in PhA (r = 0.60, P < 0.01).     

Dynamics of submaximal effort soccer instep kicking

During a soccer match, players are often required to control the ball velocity of a kick. However, little information is available for the fundamental qualities associated with kicking at various effort levels. We aimed to illustrate segmental dynamics of the kicking leg during soccer instep kicking at submaximal efforts. The instep kicking motion of eight experienced university soccer players (height: 172.4 ± 4.6 cm, mass: 63.3 ± 5.2 kg) at 50, 75 and 100% effort levels were recorded by a motion capture system (500 Hz), while resultant ball velocities were monitored using a pair of photocells. Between the three effort levels, kinetic adjustments were clearly identified in both proximal and distal segments with significantly different (large effect sizes) angular impulses due to resultant joint and interaction moments. Also, players tended to hit an off-centre point on the ball using a more medial contact point on the foot and with the foot in a less upright position in lower effort levels. These results suggested that players control their leg swing in a context of a proximal to distal segmental sequential system and add some fine-tuning of the resultant ball velocity by changing the manner of ball impact.     

Borg-Skala

The aim of this study was to analyze differences in the rate of subjectively perceived exertion for half marathon runners versus ultramarathon runners measured with the Borg scale (6–20); therefore, 21 half marathon runners (mean age 34.3 ± 7.3 years, height 177 ± 7 cm and body weight 72 ± 8.1 kg) and 16 ultramarathon runners (39.8 years, 176.1 ± 7 cm and 69.1 ± 8.2 kg) participating in the Mountainman Race in Melchseefrutt (Obwalden, Switzerland) were asked to specify the perceived exertion with the Borg scale (6–20) for the first part of the race, the second part of the race and the total race. Half marathon runners and ultramarathon runners indicated values of 14.2 and 14.7, respectively for the first part of the race, which were in the same range measured with the Borg scale (6–20). A different pattern could be detected for the second part of the race with values of 16.3 for half marathon runners and 18.6 for ultramarathon runners. The rate of total perceived exertion was higher with 17.6 for ultramarathon runners versus 15.7 for half marathon runners, whereby differences between perceived exertion in the second part of the race and the total race in the ultramarathon did not show significant differences in contrast to the half marathon, where significant differences could be detected. These findings can be embedded in previously conducted analyses for a 100 km race indicating an exponential increase of stress parameters after 75 km (e.g. creatine kinase, lactate dehydrogenase and transaminases) resulting from an acute phase reaction. Parallel analyses of biological parameters (e.g. heart rate, creatine kinase, lactate dehydrogenase and transaminases) could give further hints concerning the principal validity of the Borg scale (6–20) for ultramarathon races.     

The effect of ball-carrying technique and experience on sprinting in rugby union

Abstract

There are several ways of carrying the ball in rugby union, which could influence the speed at which a player can run. We assessed 52 rugby players (34 males, 18 females) during a maximum sprint over 30 m without the ball, with the ball under one arm, and with the ball in both hands. Timing gates were used to measure time over the initial 10 m and the last 20 m. It has previously been reported (Grant et al., 2003 Grant, S. J., Oommen, G., McColl, G., Taylor, J., Watkins, L.Friel, N. 2003. The effects of ball carrying method on sprint speed in rugby union football players. Journal of Sports Sciences, 21: 1009–1015. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) that running with the ball produces a slower sprinting speed than running without the ball. We hypothesized that the decrease in speed caused by carrying the ball would become less marked with the experience of the player. The male and female players were each divided into two groups: a “beginner” group that consisted of players in their first or second season and an “experienced” group that was composed of players who had played for more than two seasons. A 2 × 3 mixed-model analysis of variance was used to identify differences (P < 0.01) between the beginner and experienced groups in the three sprinting conditions. The times for the males for the first 10 m sprints without the ball, with the ball under one arm, and with the ball in both hands were 1.87 ± 0.08 s, 1.87 ± 0.08 s, and 1.91 ± 0.1 s for the beginners, and 1.87 ± 0.1, 1.88 ± 0.1 and 1.88 ± 0.12 for the more experienced players respectively. The times for the females for the first 10 m without the ball, with the ball under one arm, and with the ball in both hands were 2.13 ± 0.16 s, 2.19 ± 0.17 s, and 2.20 ± 0.16 s for the beginners, and 2.03 ± 0.12 s, 2.03 ± 0.09 s, and 2.04 ± 0.1 s for the more experienced players respectively. For the last 20 m of the 30-m sprint, there were differences between the different sprint conditions (P < 0.001) but no differences that were attributable to experience (P = 0.297). The times for the males over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 2.58 ± 0.19 s, 2.61 ± 0.12 s, and 2.65 ± 0.12 s for the beginners, and 2.59 ± 0.12, 2.62 ± 0.23, and 2.65 ± 0.18 s for the more experienced players respectively. The times for the females over the last 20 m without the ball, with the ball under one arm, and with the ball in both hands were 3.25 ± 0.38 s, 3.35 ± 0.42 s, and 3.40 ± 0.46 s for the beginners, and 3.04 ± 0.32 s, 3.06 ± 0.22 s, and 3.13 ± 0.27 s for the more experienced players respectively. No gender-specific differences were detected. The results of this study suggest that practising sprints while carrying a ball benefits the early phase of sprinting while carrying the ball.     

The relationship between lower body stiffness and injury incidence in female netballers

The aim of this study was to provide contemporary information on injury rates in an elite and sub-elite netball population and to explore the relationship between lower body stiffness and lower body injuries. One elite and two sub-elite teams of female netballers (n = 29) performed the vertical hop test to assess active lower body stiffness (K_vert) and myometry to assess quasi-static stiffness. Lower body injuries were monitored via self-reporting and liaison with physiotherapists. Twelve lower body non-contact injuries were sustained by 10 players, equating to 11.29 lower body injuries per 1,000 exposure hours. The most commonly injured sites were the calf (33%) and ankle (25%). No significant differences between K_vert of injured and non-injured players were reported, however, injured elite players recorded significantly higher season mean quasi-static stiffness in the soleus (p = 0.037) and Achilles (p = 0.004) than non-injured elite players. Elite and sub-elite netball players recorded a higher injury incidence than previous reports of injuries in recreational netballers. Within the constraints of the study, relatively high stiffness of the soleus and Achilles appears to be related to lower body non-contact injury incidence in female netballers, particularly at the elite level. These results provide a basis for development of injury prevention strategies.     

Electromyographic analysis of hip adductor muscles in soccer instep and side-foot kicking

ABSTRACT

A possible link between soccer-specific injuries, such as groin pain and the action of hip adductor muscles has been suggested. This study aimed to investigate neuromuscular activation of the adductor magnus (AM) and longus (AL) muscles during instep and side-foot soccer kicks. Eight university soccer players performed the two types of kick at 50%, 75% and 100% of the maximal ball speed. Surface electromyography (EMG) was recorded from the AM, AL, vastus lateralis (VL) and biceps femoris (BF) muscles of both kicking and supporting legs and the kicking motions were three-dimensionally captured. In the kicking leg, an increase in surface EMG with an increase in ball speed during instep kicking was noted in the AM muscle (p < 0.016), but not in AL, VL or BF muscles (p > 0.016). In the supporting leg, surface EMG of both AM and AL muscles was significantly increased with an increase in the ball speed before ball impact during both instep and side-foot kicks (p < 0.016). These results suggest that hip adductor muscles markedly contribute to either the kicking or supporting leg to emphasise the action of soccer kicks.     

Ground reaction forces,kinematics, and muscle activations during the windmill softball pitch

Abstract

The aims of the present study were to examine quantitatively ground reaction forces, kinematics, and muscle activations during the windmill softball pitch, and to determine relationships between knee valgus and muscle activations, ball velocity and muscle activation as well as ball velocity and ground reaction forces. It was hypothesized that there would be an inverse relationship between degree of knee valgus and muscle activation, a direct relationship between ground reaction forces and ball velocity, and non-stride leg muscle activations and ball velocity. Ten female windmill softball pitchers (age 17.6 ± 3.47 years, stature 1.67 ± 0.07 m, weight 67.4 ± 12.2 kg) participated. Dependent variables were ball velocity, surface electromyographic (sEMG), kinematic, and kinetic data while the participant was the independent variable. Stride foot contact reported peak vertical forces of 179% body weight. There were positive relationships between ball velocity and ground reaction force (r = 0.758, n = 10, P = 0.029) as well as ball velocity and non-stride leg gluteus maximus (r = 0.851, n = 10, P = 0.007) and medius (r = 0.760, n = 10, P = 0.029) muscle activity, while there was no notable relationship between knee valgus and muscle activation. As the windmill softball pitcher increased ball velocity, her vertical ground reaction forces also increased. Proper conditioning of the lumbopelvic–hip complex, including the gluteals, is essential for injury prevention. From the data presented, it is evident that bilateral strength and conditioning of the gluteal muscle group is salient in the windmill softball pitch as an attempt to decrease incidence of injury.     

A systematic review of injuries in recreational field hockey: From injury problem to prevention

ABSTRACT

The purpose of this study was to gather information from scientific literature related to all steps of Van Mechelen’s “sequence of prevention” for injuries applied to youth and adult recreational field hockey players. A systematic review was conducted in Medline via Pubmed and in SPORTDiscus via EBSCOhost. Twenty-six original studies were included. Regarding injury incidence (step 1) results showed several overall injury incidence rates (youth: 1.47 per 1,000 Athlete Exposure (AE) time-loss (TL) injury up to 11.32 per 1,000 AE TL ánd non-time loss (NTL) injury, adults: 2.2 NTL injury per 1,000 AE, 15.2 injury per 1,000 hours of sports participation). Considering games and practices, most injuries were sustained in games (youth: 4.9, adults: 7.87 per 1,000 AE). Considering body parts, highest injury incidence rates were found in body parts in the lower extremities (youth: knee injuries in games (0.33 per 1,000 AE), adults: hamstring injuries in pre-season (0.75 per 1,000 AE)) and injuries in the head/face/eye (youth: 0.66 and adults: 0.94 head/face/eye, 0.71 head/face and 0.63 concussion per 1,000 AE). Regarding aetiology (step 2), no studies were found. Regarding the efficacy of available interventions (step 3 and 4), one study was found among youth players, describing a warm-up programme.