Water polo is a competitive team sport that dates back to the mid-19th century in England and Scotland, later becoming the first team sport to debut in the 1900 Olympic games (1). It has traditionally been a European-dominated sport (Hungary, Spain, Italy, Croatia, Serbia, Greece, Russia), but it has grown in popularity in the United States, Australia, Canada, and Asia over the past few decades. Today’s sport of water polo is played in a pool with dimensions varying from 20 m to 30 m (length) × 10 m to 20 m (width), depending on level of competition and pool size, with minimum depth of 1.8 m. Maximum pool length for men is 30 m and for women is 25 m. There are seven players on each side, and games consist of four 8-min quarters (49). As a sport, water polo is a combination of swimming, throwing/shooting, and grappling. It is very physiologically demanding because of the frequent bursts of activity (about 15 s) followed by brief lower intensity periods (less than 20 s). Given the combination of skills required, both training methods and injuries in water polo have a wide breadth. Although there is generally minimal evidence-based information available, the authors attempt to highlight the current knowledge in regard to water polo injuries and training methods.
Water Polo Training Methods
Water polo is a blend of high-intensity bursts of effort, endurance, throwing, and body contact/grappling. Therefore, training often attempts to enhance a variety of abilities, including anaerobic power, aerobic fitness, muscle strength, and water polo-specific skills.
Swimming is the core skill required in water polo and forms the foundation of training. As opposed to traditional competitive swimming, water polo is a combination of sustained swimming endurance and shorter bursts of high-intensity sprints that necessitates both aerobic and anaerobic fitness. Similar to swimmers, water polo players complete a base of swimming training to build aerobic endurance; however, water polo players must use a large proportion of their training above the lactate threshold to train for the repetitive bursts of sprinting. Thus, lactate threshold training and resultant “lactate endurance,” which is acquired, are important in water polo. Greater lactate endurance corresponds with enhanced quality of defensive duties, while both lactate endurance and advanced swim sprinting capacity correlate with superior offensive performance (24,26,45). One common way to train at the lactate threshold and augment lactate endurance is through high-intensity interval training (HIIT) swimming workouts. D’Ercole et al. and Botonis et al. (5,10) found that short rest intervals (10 to 20 seconds) during HIIT workouts resulted in significant improvements in swimming performance in both elite and non-elite water polo players. Greater gains in aerobic performance were obtained with long HIIT swimming intervals (4 × 4 min with 3-min active recovery between) at exercise intensity that exceeds lactate threshold. However, HIIT with higher repetition of shorter swims (16 × 100 m), similar exercise intensity, and shorter recovery time (20 seconds between) may induce smaller, yet practically significant, endurance gains. To the authors’ knowledge, there are no specific studies that investigate training effects of “head up” versus “head down” swimming styles that are both used in water polo.
Another way to potentially increase lactate endurance and performance in water polo athletes is through the “live high, train low” (LHTL) altitude training philosophy that is used in other sports. Garvican-Lewis et al. (16) evaluated the effects of this training methodology on hemoglobin mass in elite water polo players. They found that over a 6-month period, simulated LHTL exposures (normobaric, hypoxic facility) of less than 2 wk each resulted in increased hemoglobin mass by 4%, which correlated with improved shuttle swim test time. The shuttle swim test is a validated and reliable assessment of swimming fitness for water polo players (28). In summary, water polo requires swimming skills with adequate lactate endurance to be successful. Therefore, the core of training in water polo revolves around enhancing these abilities.
There are several water polo-specific activities that require focused training. The first of these activities is lower limb muscle performance in the form of vertically directed kicking under water. This allows the athlete to propel his or her upper body and torso out of the water to perform many of the essential tasks of water polo, including passing, shooting, grappling with an opponent, and shot blocking. The main type of vertical kicking in water polo is a rotational movement known as the “eggbeater kick.” It is a cyclical action of the lower legs, which is mainly performed by the knees, with alternating rotations of the legs, similar to an eggbeater (35). The principle function of the eggbeater kick is to hold the upper body and torso out of the water at a relatively constant level (Fig. 1); however, there also are boosts or “jumps” which are explosive upward movements to achieve maximum momentary height or lateral movement (Fig. 2) (44). These jumps happen by concluding the eggbeater motion with a simultaneous, powerful kick of both legs downward and backward toward the bottom of the pool (modified breaststroke kick). Gobbi et al. (18) analyzed the components of jumps in expert versus intermediate players and found that by generating greater power and velocity, the expert players reduced the temporal variability of motor commands during the jump, making it more effective.
Given that the eggbeater kick and jumps require specialized movement and strength of the legs, training is essential. This is often done through some type of weight or resistance training. Melchiorri et al. (29) propose a method for training and measuring of the eggbeater kick effectiveness by using a jacket with attached weights of variable load. Significant improvements in time to exhaustion were measured at all loads in the elite compared with nonelite athletes. Other training methods, such as holding weights in the hands above the water or emptying water jugs, are often used. Jumps also can be trained in a similar fashion with weights (7 to 10 kg) attached to a jacket or belt. The athlete then repeats a series of jumps with a short rest period in between each and a longer rest period between each set (18).
Another essential skill in water polo is throwing and catching the ball. Throwing can be broken down further into both passing and shooting. Passing is a lower-velocity action for the purpose of transferring the ball to a teammate. As such, it is usually used as a warm-up activity for the arms before shooting drills or during scrimmaging/game activities. Practicing passing also helps develop catching skills. In contrast, shooting is much more forceful and is obviously an essential action for scoring goals. Shooting skills are proven to be enhanced by a multitude of different methods — repetition, drills, resistance, and medicine balls. One study tested the differences between some of these training methods by comparing a group using medicine balls only versus a group using a combination of medicine balls and regular water polo balls. The groups were matched for overall training workload, and no significant difference in throwing velocity was found between the groups; however, both showed statistically significant improvements. This suggests that overall workload, and not necessarily training type, may be the most important factor in enhancing shooting velocity and skills (26). Usually, some combination of repetition (with or without a goalkeeper), drills, resistance, and medicine ball training is used.
Similar to soccer, water polo is a sport in which penalty shots are a considerable component of the game, and they can often be a factor in determining the outcome (46). Consequently, training around this specific situation can result in improved performance. Using a “preperformance” or “preshot” routine, as commonly used in golf, soccer (penalty kicks), basketball (free throws), or baseball (batting), has been shown to improve penalty shot performance. In water polo, a preperformance routine consisting of a concentration cue, relaxation (deep breaths), imagery, and a cue word showed improvement in penalty shot performance in all subjects in one small study (25). Therefore, it may be beneficial to incorporate mental aspects of shooting into training programs.
It also is important to note that water polo is unique among throwing sports in that players will frequently catch, shoot, or pass with their nondominant arm. Use of the nondominant arm may be necessitated by location in the water relative to the defender(s) and the goal, especially because water polo players are never allowed to touch the ball with two hands simultaneously (other than the goalkeeper inside the 5-m line). Therefore, gaining skill at using both arms during training is critical.
Another component of water polo training may be dryland (out-of-water) or in-water strengthening activities. When combined with traditional water polo training (sport-specific drills and swimming), dedicated strength training may provide improvements in water polo-specific parameters. de Villarreal et al. (42) examined the effects of a 3-d·wk−1, 60-min dryland versus in-water training session before normal water polo activities and found significant improvements in in-water boost, countermovement jump, swimming agility, and maximal dynamic strength tests in both groups. Other similar studies by the same group also found an improvement with a combination of in-water strengthening and dryland plyometric training as well as power training (bench press, squats, pull-ups, etc.) on similar water polo-specific parameters (36,43). Yet another similar study found that a 16-wk lower-body resistance and power-oriented training program produced significant improvements in water polo-specific parameters compared with a control group of traditional in-water training only (37). In addition, strengthening may help prevent both overuse and acute injuries, as is the case in many sports; however, there is a paucity of data specific to water polo players. Overall, it appears that adding specific strength training, either dryland or in-water, may be effective at increasing water polo performance and possibly preventing injury.
The final key component of water polo training is nutrition. While there is generally a dearth of literature on this subject in regard to water polo, there are a few articles that provide some guidance on nutrition for water polo players. Also, some of the same principles of nutrition for swimmers may be applied given the training overlap of both sports. Just as in swimmers, water polo players require a high-caloric diet to support their high-caloric expenditure due to large, intense training volumes, and demanding matches. Accordingly, higher caloric amounts (especially carbohydrates) are recommended during large training days or training periods to aid in performance and enhance recovery, while taper or rest periods leading up to important matches may require decreased caloric intake (47). Performance may be hindered if intake is not appropriately matched with expenditure. Because larger body mass may offer a physical advantage in water polo, nutritional strategies that promote lean muscle mass are important (9). While there are no water polo-specific recommendations, consuming 20 to 25 g of protein in the immediate postexercise period is known to be helpful in other sports (3). There is insufficient evidence on the effects of ergogenic supplements (i.e., creatine monohydrate) on body mass and performance in water polo players.
Even though exercising in water reduces sweat losses compared with land-based activities, hydration is still important in water polo. This is especially apparent in venues with warmer water, humid indoor settings, and hot temperatures at outdoor pools (40). In addition, micronutrient deficiencies are somewhat common in swimmers (and likely water polo players). The most prevalent are vitamin D and iron, which can potentially limit training performance and impair immune system function (14,32). Hence, a nutrition plan should not be overlooked in water polo players because poor nutrition can likely have a negative impact on training and performance.
Water Polo Injuries
As described earlier, water polo is a unique combination of swimming and throwing, elements of quick bursts of energy on top of demanding stamina, and frequent physical contact. This combination not only predisposes water polo athletes to overuse injuries from the constant demand of the eggbeater kick and frequent overhead movements from swimming, throwing, and defending, but also given the intense physical contact and high velocities (60 to 70 km·h−1) reached by the water polo ball, athletes are prone to more acute injuries as well. This section is meant to highlight some of the injuries encountered in water polo (Table). The authors have divided this section into separate regions of the body, starting with the head and face because these are the most commonly injured body parts (22,30).
Head and Face
Water polo is an inherently physical sport with a great amount of contact between players and minimal protective equipment. According to Fédération Internationale de Natation (FINA), the international federation governing aquatic sports, only a swimming cap with malleable ear protectors may be worn (Fig. 3) (49). The ear protectors help prevent any direct trauma to the ear or ear drum, but the cap itself is more of a team identifier, rather than any form of protection to the head. This lack of protection leaves water polo athletes prone to contusions, fractures, and lacerations to the head and face. During the 2004 Olympic Games in Athens, Greece, the majority of water polo injuries affected the head (56% of injuries reported) with all injuries being incurred because of contact with another player (22). Of these injuries, the most common type of injury was a contusion followed by laceration/abrasion (22). Traumatic perforation of the ear drum is a common injury in water polo, despite ear protectors, and is often the result of a slap on the side of the head. Usually, this injury will heal well without any residual effects, but during the healing phase, players should be kept out of the water (11,41). More significant blows can result in nasal or facial bone fractures, which require more immediate evaluation and treatment (15). In addition to acute facial injuries, prolonged exposure to water and frequent attempt to clean the ear canal predispose water polo players to develop acute otitis externa (swimmer’s ear) (40).
According to the International Dental Federation (FDI), water polo is classified as a medium-risk sport for dental injury and with frequent body contact the risk for injury is high (13). Despite this, FINA does not require the use of a mouth guard, with only 7.7% of athletes reported wearing a mouth guard, according to one survey (19). In this survey consisting of 415 elite Swiss water polo players, nearly 50% reported witnessing a dental injury in water polo, with 21% reported having suffered a tooth injury while playing water polo, the most common being tooth fracture (19). Given this information, it seems surprising that mouth guards are not part of the equipment required by FINA regulations. Perhaps this is due to the perception among players that minimal equipment is preferred or that mouthguards could impair breathing while swimming.
Ocular injuries are relatively common in water polo (2,39). Corneal abrasions can occur from a scratch to the eye with a fingernail. Players may require antibiotic eyedrops for treatment (7). Most organizations require a “nail check” with a referee before competition to ensure proper trimming of nails to reduce prevalence of such nail-related injuries. Hyphemas (bleeding into anterior chamber of eye) can occur with a direct blow to the eye. With more significant blows, globe rupture or orbital fracture may occur. Chronic ocular issues arise mainly from eye irritation due to chlorinated water, especially because water polo players cannot wear swim goggles due to the risk of periorbital injury. In addition, ocular infections can occur in water polo. Athletes wearing soft contact lenses are especially at risk of developing pseudomonas infection and acanthamoeba keratitis (7,20). Pseudomonas infection can be treated with fluoroquinolone ophthalmic antibiotics and disposal of contact lenses. Acanthamoeba infection is rare, but serious. Symptoms may include eye pain/redness, blurred vision, light sensitivity, foreign body sensation, and excessive tearing. Suspected patients should be referred to an ophthalmologist immediately for evaluation, because early detection is essential. Prevention of ocular infection consists of contact lens removal during swimming with use of prescription sports eyewear instead (i.e., Rec Specs) or thorough disinfection of lenses following swimming.
As in many other contact sports, water polo players are susceptible to sustaining a concussion. These usually occur from a direct blow to the head, either from contact with another player or the water polo ball. A recent survey study from UC Irvine with more than 1500 USA Water Polo member respondents demonstrated the high prevalence of concussion in the sport. Thirty-six percent reported getting at least one concussion while playing water polo, with an average of more than two concussions per person (4). Standard evaluation, treatment, and return-to-play protocols should be used for those athletes suspected of sustaining a concussion.
As evidenced by the reported injuries during the 2004 Olympic Games and the 2009 FINA World Championships, the upper extremity is the next most commonly injured body part in water polo. The upper extremity (shoulder, elbow, wrist, and hand) accounted for 28% of the injuries in the 2004 Olympics and 45% of the reported injuries during the 2009 FINA World Championships (22,30). Of the upper extremity injuries, shoulder pain is the most prevalent and best studied.
While there is a wealth of information available in regard to shoulder pain in the overhead athlete, most of the research is in baseball, basketball, football, tennis, etc., with a relatively limited amount of articles specific to water polo. In 2009, Webster et al. (50) published a systematic review of shoulder pain in water polo and found a “high incidence of shoulder pain in water polo,” but were unable to draw conclusions regarding causation. Shoulder pain is very common in swimming, with the shoulder being the most commonly injured body part in both the 2009 and 2013 FINA World Championships when taking all aquatics into account (30,31). However, the question in regard to water polo is whether shoulder pain and injuries arise from swimming, repeated throwing, or a combination of both.
While not specific to water polo, overhead athletes are prone to develop shoulder pain and impingement or tearing of the rotator cuff (34). Inherent to the overhead throwing motion, when the arm is abducted and maximally externally rotated, as it is in the late-cocking phase, the humeral head can sublux anteriorly putting stress on, and creating microtrauma to, the anterior static restraints of the shoulder and scapula (34). It has been hypothesized that this increase in mobility can cause greater stress on shoulder structures and a subsequent imbalance in shoulder stabilizing muscles (16,34,50). Witwer and Sauers (51) found that swimmers have a bilateral increase in shoulder mobility, but water polo players typically have a unilateral increase in mobility and range, predominantly in their throwing arms. This increase in mobility can result in impingement of the rotator cuff undersurface against the posterior glenoid rim, leading to posterior internal impingement and hence shoulder pain (17,34). While there are several unique aspects of water polo that may predispose athletes to shoulder pain and injuries (i.e., different swimming stoke compared to freestyle swimming, elevated swimming posture with head out of water, throwing a large ball with no base of support in the water, frequent overhead movements in defensive play, large forces absorbed by the shoulder when blocking a shot or from contact with another player, etc.), the lack of available research makes it difficult to discern the exact contributing factors to subacute and chronic shoulder pain in water polo. More acute shoulder injuries are due to subluxation/dislocation of the glenohumeral and acromioclavicular (AC) joints. These can result in ligament/capsule tears, labral injuries, and shoulder instability (15).
Injuries to the elbow, wrist, and hand are less frequent than the head/face and shoulder, but the most common injury types remain contusions, lacerations, and abrasions (22,30). Franić et al. (15) notes that ulnar collateral ligament injuries (gamekeeper’s thumb), osteochondritis dissecans of the capitellum, de Quervain’s tenosynovitis, and lacerations or dislocations of the interphalangeal and metacarpophalangeal joints, and fractures of the phalanges and metacarpal bones are the most common elbow, wrist, and hand injuries in water polo. There is a paucity of published water polo injuries, but a case report describes a water polo goalie that blocked a shot with an outstretched arm causing hyperextension of the elbow and subsequent elbow pain later developing osteochondritis of the capitellum (38). Other reported injuries include sternal fracture and a scapular stress fracture felt to be secondary to the continuous scapular motion and recruitment of the scapular stabilizers to maintain buoyancy during the 2004 Olympic Games (12,22).
Lower extremity injuries are less common, but still important to consider, with contusions and sprains as the most common injury types (22,30). Water polo is unique in the use of the eggbeater kick to help athletes tread water and propel themselves out of the water as required for both offense when shooting as well as a defensive posture to block shots or passes. Expert water polo players can produce a considerable amount of explosive force over a very short time (161 ms) to propel themselves about 1 m above the water (18). It seems intuitive that this large amount of repetitive force may lead to hip/knee/foot pain, similar to breaststroke swimmers, but the authors were not able to find any published data on this topic in water polo. Prevention and treatment should focus on proper eggbeater technique and adequate warm-up of the legs before play (21).
Although not common, injuries to the spine (usually cervical or lumbar) may occur. Acute cervical injuries may be due to extreme blows or hitting the head while diving into the pool. As such, all pools should have spine boards and cervical collars available along with trained personnel. Chronic cervical injuries (muscle pain, radiculopathy, etc.) may occur due to repetitive rotation and lifting of the head during swimming. Chronic lumbar spine problems (muscle pain, disc herniations, etc.) can arise from significant lumbar forces generated during shooting and passing (8).
Injury to the abdomen and groin can occur in water polo as a result of underwater grappling and kicking. This is difficult to police during matches because the referees are located out of the water on the pool deck and therefore underwater activities are often not visualized. Grappling injuries may include trauma to intra-abdominal organs (i.e., spleen), genitals (men), and breasts (women).
There also are some medical issues that should be taken into special consideration for water polo players. Several of these are related to chlorinated/brominated pools. There is strong evidence suggesting that acute and/or chronic exposure can manifest as upper respiratory dysfunction (chronic rhinitis, sneezing, irritated nasal sinuses, runny nose, nasal obstruction, and sinusitis), lower respiratory dysfunction (breathing difficulty, wheezing, cough, chest tightness, and abnormal spirometry), eye irritation, and headaches (6,23).
Water polo players are susceptible to different dermatologic conditions given their substantial amount of time spent in the water and in moist environments. Some dermatoses are organism-related, such as swimming pool granulomas (atypical Mycobacterium infection), that may occur overlying bony prominences and are often found in the upper extremities (especially the fingers). “Hot tub” (pseudomonas aeruginosa) folliculitis is another skin infection that usually appears within 8 to 48 h of exposure to contaminated water. As aquatic athletes, water polo players also are particularly vulnerable to other common skin infections, such as molluscum contagiosum (“water warts”), tinea pedis (“athlete’s foot”), and plantar warts (48). Noninfectious dermatologic conditions encountered in water polo are frictional dermatoses such as “pool palms” (recurrent contact on rough pool surfaces with hands/feet) and irritation from rubbing of the chin on the shoulder when turning the head to breathe (52). Finally, outdoor aquatic athletes are at increased risk for skin cancer, possibly potentiated by pool water chemicals (33). Therefore, it is important to counsel outdoor water polo players on adequate use of water-resistant or waterproof sunscreen.
Water polo is a unique team sport combining swimming sprints and eggbeater kicks with frequent overhead movements and throwing in the setting of regular physical contact and minimal protective equipment. Accordingly, a wide variety of training methods attempt to enhance all of these skill sets. This usually includes some combination of aerobic/anaerobic fitness (via swimming), sport-specific skills, strengthening, and nutrition. While there is limited published information regarding injuries in water polo, it is clear that the inherent physical contact is responsible for the majority of acute injuries, most frequently being injuries to the head and face. The high incidence of shoulder pain in water polo is likely related to increased shoulder mobility and subsequent instability and stress on shoulder structures, yet the underlying causation is not certain. In addition, there are several medical illnesses that are important to consider in water polo players due to the aquatic environment. In conclusion, it is apparent that we have made good strides in the care of water polo athletes; however, continued research with regard to injury prevention and perhaps improved training methods is needed to better care for these athletes and to help enhance their performance.
The authors declare no conflict of interest and do not have any financial disclosures.
1. Aquatics: History of Water Polo at the Olympic Games. International Olympic Committee. 2015.
2. Barr A, Baines PS, Desai P, MacEwen CJ. Ocular sports injuries: the current picture. Br. J. Sports Med
. 2000; 34:456–8.
3. Betts JA, Williams C. Short-term recovery from prolonged exercise: exploring the potential for protein ingestion to accentuate the benefits of carbohydrate supplements. Sports Med
. 2010; 40:941–59.
4. Blumenfeld RS, Winsell JC, Hicks JW, Small SL. The epidemiology of sports-related head injury and concussion in water polo. Front Neurol
. 2016; 7:98.
5. Botonis PG, Toubekis AG, Platanou TI. Concurrent strength and interval endurance training in elite water polo players. J. Strength Cond. Res
. 2016; 30:126–33.
6. Bougault V, Turmel J, Levesque B, Boulet LP. The respiratory health of swimmers. Sports Med
. 2009; 39:295–312.
7. Bremond-Gignac D, Chiambaretta F, Milazzo S. A European perspective on topical ophthalmic antibiotics: current and evolving options. Ophthalmol. Eye Dis
. 2011; 3:29–43.
8. Brooks JM. Injuries in water polo. Clin. Sports Med
. 1999; 18:313–9.
9. Cox G, Mujika I, Hoogenband CR. Nutritional recommendations for water polo. Int. J. Sport Nutr. Exerc. Metab
. 2014; 24:382–91.
10. D’Ercole C, Gobbi M, D’Ercole A, et al. High intensity training for faster water polo. J. Sports Med. Phys. Fitness
. 2012; 52:229–36.
11. Dominguez RH. Water polo injuries. Clin. Sports Med
. 1986; 5:169–83.
12. Donaldson LD. Scapular stress fracture in water polo: a case report. Sports Health
. 2012; 4:502–3.
13. Federation Dentaire International (FDI). Commission on dental products. Working party No. 7;1990.
14. FINA Nutrition Expert Panel. FINA-Yakult consensus statement on nutrition for the aquatic sports. Int. J. Sport Nutr. Exerc. Metab
. 2014; 24:349–50.
15. Franić M, Ivković A, Rudić R. Injuries in water polo. Croat Med J
. 2007; 48:281–8.
16. Garvican-Lewis LA, Clark SA, Polglaze T, et al. Ten days of simulated live high: train low altitude training increases Hb mass in elite water polo players. Br. J. Sports Med
. 2013; 47(Suppl 1):i70–3.
17. Giombini A, Rossi F, Pettrone FA, Dragoni S. Posterosuperior glenoid rim impingement as a cause of shoulder pain in top level water polo players. J. Sports. Med Phys Fitness
. 1997; 37:273–8.
18. Gobbi M, D’Ercole C, D’Ercole A, Gobbi F. The components of the jumps in expert and intermediate water polo players. J. Strength. Cond. Res
. 2013; 27:2685–9.
19. Hersberger S, Krastl G, Kühl S, Filippi A. Dental injuries in water polo, a survey of players in Switzerland. Dent Traumatol
. 2012; 28:287–90.
20. Jiang C, Sun X, Wang Z, Zhang Y. Acanthamoeba keratitis: clinical characteristics and management. Ocul Surf
. 2015; 13:164–8.
21. Jones JH. Swimming overuse injuries. Phys. Med. Rehabil. Clin. N Am
. 1999; 10:77–94.
22. Junge A, Langevoort G, Pipe A, et al. Injuries in team sport tournaments during the 2004 Olympic Games. Am. J. Sports. Med
. 2006; 34:565–76.
23. Khodaee M, Edelman GT, Spittler J, et al. Medical care for swimmers. Sports. Med. Open
. 2016; 2:27.
24. Kontic D, Zenic N, Uljevic O, et al. Evidencing the association between various swimming capacities and performance indicators in water polo, a multiple regression study. J. Sports. Med. Phys. Fitness
. 2016; 13: [Epub ahead of print].
25. Marlow C, Bull SJ, Heath B, Shambrook CJ. The use of a single case design to investigate the effect of a pre-performance routine on the water polo penalty shot. J. Sci. Med. Sport
. 1998; 1:143–55.
26. Marques MC, Liberal SM, Costa AM, et al. Effects of two different training programs with same workload on throwing velocity by experienced water polo players. Percept. Mot. Skills
. 2012; 115:895–902.
27. Meckel Y, Bishop D, Rabinovich M, et al. Repeated sprint ability in elite water polo players and swimmers and its relationship to aerobic and anaerobic performance. J. Sports. Sci. Med
. 2013; 12:738–43.
28. Melchiorri G, Manzi V, Padua E, et al. Shuttle swim test for water polo players: validity and reliability. J. Sports. Med. Phys. Fitness
. 2009; 49: 327–30.
29. Melchiorri G, Viero V, Triossi T, et al. Testing and training of the eggbeater kick movement in water polo: applicability of a new method. J. Strength. Con. Res
. 2015; 29:2758–64.
30. Mountjoy M, Junge A, Alonso JM, et al. Sports injuries and illnesses in the 2009 FINA World Championships (Aquatics). Br. J. Sports. Med
. 2010; 44:522–7.
31. Mountjoy M, Junge A, Benjamen S, et al. Competing with injuries: injuries prior to and during the 15th FINA World Championship 2013 (aquatics). Br. J. Sports. Med
. 2015; 49:37–43.
32. Mountjoy M, Sundgot-Borgen J, Burke L, et al. The IOC consensus statement: beyond the Female Athlete Triad—Relative Energy Deficiency in Sport (RED-S). Br. J. Sports. Med
. 2014; 48:491–7.
33. Nelemans PJ, Rampen FH, Groenendal H, et al. Swimming and the risk of cutaneous melanoma. Melanoma Res
. 1994; 4:281–6.
34. Paley KJ, Jobe FW, Pink MM, et al. Arthroscopic findings in the overhand throwing athlete: evidence for posterior internal impingement of the rotator cuff. Arthroscopy
. 2000; 16:35–40.
35. Platanou T. On-water and dryland vertical jump in water polo players. J. Sports. Med. Phys. Fitness
. 2005; 45:26–31.
36. Ramos-Veliz R, Requena B, Suarez-Arrones L, et al. Effects of 18-week in-season heavy-resistance and power training on throwing velocity, strength, jumping, and maximal sprint swim performance of elite male water polo players. J. Strength Cond. Res
. 2014; 28:1007–14.
37. Ramos-Veliz R, Suarez-Arrones L, Requena B, et al. Effects of in-competitive season power-oriented and heavy resistance lower-body training on performance of elite female water polo players. J. Strength Cond Res
. 2015; 29:458–65.
38. Rod E, Ivkovic A, Boric I, et al. Acute hyperextension/valgus trauma to the elbow in top-level adult male water polo goalkeepers: a cause of osteochondritis disecans of the capitellum? Injury
. 2013; 44(Suppl 3):S46–8.
39. Rodriguez JO, Lavina AM, Agarwal A. Prevention and treatment of common eye injuries in sports. Am. Fam. Physician
. 2003; 67:1481–8.
40. Rosenfeld RM, Schwartz SR, Cannon CR, et al. Clinical practice guideline: acute otitis externa. Otolaryngol Head. Neck Surg
. 2014; 150(Suppl 1):S1–S24.
41. Rybak LP, Johnson DW. Tympanic membrane perforations from water sports: treatment and outcome. Otolaryngol Head. Neck Surg
. 1983; 91:659–62.
42. Sáez de Villarreal E, Suarez-Arrones L, Requena B, et al. Effects of dry-land vs. in-water specific strength training on professional male water polo players’ performance. J. Strength. Cond. Res
. 2014; 28:3179–87.
43. Sáez de Villarreal E, Suarez-Arrones L, Requena B, et al. Enhancing performance in professional water polo players: dryland training, in-water training, and combined training. J. Strength. Cond. Res
. 2015; 29:1089–97.
44. Sanders R. A model of kinematic variables determining height achieved in water polo ‘boosts’. J. Appl. Biomech
. 1999; 15:270–83.
45. Sekulic D, Kontic D, Esco MR, et al. Sport-specific conditioning variables predict offensive and defensive performance in high-level youth water polo athletes. J. Strength Cond. Res
. 2016; 30:1316–24.
46. Smith HK. Penalty shot importance, success and game context in international water polo. J. Sci. Med. Sport
. 2004; 7:221–5.
47. Stellingwerff T, Maughan RJ, Burke LM. Nutrition for power sports: middle-distance running, track, cycling, rowing, canoeing/kayaking, and swimming. J. Sports Sci
. 2011; 29(Suppl 1):S79–89.
48. Tlougan BE, Podjasek JO, Adams BB. Aquatic sports dermatoses: part 1. In the water: freshwater dermatoses. Int. J. Dermatol
. 2010; 49:874–85.
49. Water Polo Rules. Federation Internationale De Natation
50. Webster MJ, Morrie ME, Galna B. Shoulder pain in water polo: a systemic review of the literature. J. Sci. Med. Sport
. 2009; 12:3–11.
51. Witwer A, Sauers E. Clinical measures of shoulder mobility in college water-polo players. J. Sports. Rehabil
. 2006; 15:45–47.
52. Wong LC, Rogers M. Pool palms. Pediatr. Dermatol
. 2007; 24:95.