We tested the hypothesis that menthol application would reduce the magnitude and initiation of sweating via excitation of cold-sensitive afferent pathways and concurrently via a cross-inhibition of heat loss pathways in acclimatized (swimmers, SW) and non acclimatized (control, CON) subjects in cool water. It was expected this effect to be exaggerated in SW subjects. Eight SW and eight CON subjects cycled at 60% of their VO(2)max, as long as to reach 38 degrees C in rectal temperature (Tre), without or with (4.6 g per 100 ml of water) all-body application of menthol sediment. Heart rate (HR), Tre, sweating rate (SwR), the proximal-distal skin temperature gradient (TSk(f-f)), and oxygen consumption (VO(2)) were measured continuously. VO(2) and HR were similar between groups and conditions. Menthol increased TSk(f-f), Tre threshold for SwR [+0.32 (0.01) degrees C] and Tre gain, while menthol reduced exercise time by 8.1 (4.1) min. SW group showed higher changes in Tre threshold for SwR [+0.50 (0.01) degrees C for SW vs. +0.13 (0.03) degrees C for CON], higher Tre gain, lower time for Tre increase and shorter exercise time [-10.7 (7) min for SW vs. -4.9 (4) min for CON] in menthol condition. Upon exercise initiation, previously applied menthol on the skin seems to induce vasoconstriction, results in a delayed sweating, which in turn affects the rectal temperature. Acclimatized subjects showed higher delay in SwR and earlier rise in Tre, which most probably is due to the inter-group differences in cold receptors activity.

The purpose of the study was to examine changes in performance and match-induced fatigue over a 27-week training period. Eight national-level water-polo players performed a 5 x 200 m swimming test to calculate velocities corresponding to blood lactate concentration of 4.0, 5.0 and 10.0 mmol.l-1 at three testing periods: i) baseline, ii) end of the pre-season (8 weeks of 4 x 4 min swimming bouts), iii) end of the in-season (8 weeks of 8 x 20 m swimming sprints). During each testing period, four competitive matches were played and repeated sprints (8 x 20 m), 400 m swimming, and shooting accuracy were evaluated at the pre- and post-match. Repeated sprint tests were also conducted at mid-game. Analysis of variance for repeated measures was used to detect changes among training periods and within games. Swimming velocities corresponding to 4.0, 5.0 and 10.0 mmol.l-1 were increased after the pre-season by 9%, 7.7%, and 6.7% (p < 0.01) and decreased following the in-season compared to the pre-season by 8.9%, 7.0% and 3.3% (p < 0.01), respectively. Pre-match repeated sprints and 400 m performance were improved after the pre-season by 4.3% and 3.8% (p < 0.01) and decreased by ~3% after the in-season compared to the pre-season (p < 0.01). Mid- and post-match repeated sprint performance was improved after the pre-season by 4.8 ± 1.4% and 4.4 ± 1.1% and remained unchanged after the in-season compared to the pre-season. Post-match 400 m speed was improved by 3.2% after the pre-season (p < 0.01) and decreased by 2.8% after the in-season (p = 0.04).Pre-season training improved players’ aerobic endurance and performance. Intensified in-season training decreased aerobic power, endurance, and pre-match performance while maintaining match repeated sprint performance.

Due to its physiological and psychological recuperative effects, sleep is an integral part of recovery for human beings and for athletes particularly. 1 Recent recommendations suggest that healthy adults should obtain 7-9 h, 2 while athletes should receive 9-10 h of total sleep to cope with the increased need for recovery. 3 However, research studies that have investigated the effects of nocturnal sleep quantity on athletic performance indicate that due to numerous constraints, athletes do not receive an adequate nighttime sleep. 4 The poor sleep quantity has been attributed to several reasons such as the training schedule and training load, light exposure, nervousness and mood disturbances as well as increases in physical and mental stress. [5][6][7] In addition to the inadequate quantity of sleep, many athletes present low sleep quality. 8,9 For instance, Knufinke et al. 9 showed that sleep efficiency of elite-level athletes was below 85% during 2 out of 7 nights, which is considered the upper limit of poor recovery. 10

Botonis, PG, Toubekis, AG, and Platanou, TI. Physiological and tactical on-court demands of water polo. J Strength Cond Res XX(X): 000-000, 2018-The purpose of the present review is to provide a quantification of the specific game's activities performed by elite water polo players and a comprehensive overview of the physiological requirements reflecting physical and tactical on-court demands in water polo. Game analysis demonstrates that various swimming movements occur throughout a match play, although approximately 50% of these are recorded in horizontal body position. The various offensive and defensive tactical actions transiently modify the playing intensity, which overall corresponds to the players' lactate threshold. Even play corresponds to 60% of total game actions, whereas the respective percentage of power-play and counterattacks may exceed 30%. The ability to perform high-intensity activities with short recovery periods is critical for water polo players. Elite water polo players present a high level of aerobic power and endurance as indicated by their maximal oxygen uptake and speed at the lactate threshold. Depending on the positional roles, outfield players are characterized as centers or peripherals. The overall physiological load seems to be similar between players at various positions, despite that centers execute more dynamic body contacts, whereas peripherals more swimming bouts. Despite limitations concerning the experimental setting, the current findings indicate that the incidence of fatigue deteriorates playing intensity and performance. Nonetheless, data from the reviewed studies should be cautiously interpreted because in some of the studies, players' substitutions were not allowed. A high conditioning level is essential for water polo, as it is associated with superior technical and tactical efficacy and lower decline of physical or technical performance within the game.

This study compared the effects of different high-intensity interval training (HIIT) intervals performed concurrently with strength and specific water polo training on performance indices of elite players. During the precompetition season, 2 water polo clubs were assigned to either HIIT of 4 × 4 minutes (n = 7, HIIT4 × 4) or HIIT of 16 × 100-m swimming efforts (n = 7, HIIT16 × 100). Both clubs applied the swimming (6% above the speed corresponding to blood lactate concentration of 4.0 mmol · L) and strength training (85-90% of 1 repetition maximum, 5 repetitions, 4 sets) twice per week concurrently with specific water polo training. Before and after the 8-week intervention period, maximal bench press strength was measured and a speed-lactate test (5 × 200 m) was performed to determine the speed corresponding to lactate concentration of 4.0, 5.0, and 10.0 mmol · L(-1). Maximal strength was improved in both groups (HIIT4 × 4: 14 ± 4% vs. HIIT16 × 100: 19 ± 10%). Improvements in speed corresponding to 4.0, 5.0, and 10.0 mmol · L(-1) were shown only after HIIT4 × 4 (9 ± 5, 8 ± 3, 7 ± 2%, respectively; p < 0.01). However, HIIT16 × 100 was more effective in the differential velocity between 10.0 and 5.0 mmol · L(-) development (19 ± 20%, p = 0.03). During the precompetition season, HIIT and strength training together with specific water polo training performed concurrently improves muscle strength and allows specific adaptations enhancing swimming performance of elite water polo players.