Venckunas Tomas, Achramavicius Justas
Institute of Sport Science and Innovations, Lithuanian Sports University, LT-44221 Kaunas, Lithuania.
Sports (Basel). 2024 Apr 28;12(5):121. doi: 10.3390/sports12050121.
The underwater phase (UP) is highly important for overall swimming performance in most swimming events. However, the metabolic effects of the prolonged UP remain unclear. The purpose of this cross-sectional study was to compare the blood lactate response to submaximal front-crawl swimming with short and extended UP. Twelve (four females) junior competitive swimmers (aged 15.4 (1.4) years) undertook 200 m front-crawl swim trials in a 25 m pool at a pre-determined "anaerobic threshold" velocity on two occasions using short (<5 m) and extended (12.5 m) UP after each turn. Pacing and total time were ensured to be identical between the trials. Capillary blood lactate response was measured. Testing for 25 m swim time with <5 m and 12.5 m UP was conducted on a separate occasion. When athletes undertook and extended UP after each propulsion from the wall, their post-exercise blood lactate concentration reached 7.9 (2.1) mmol/L, more than two times higher than the response to trial with short UP ( < 0.001). All-out 25 m swimming with <5 m or 12.5 m UP disclosed no difference in locomotion velocity ( > 0.05). In conclusion, extending UP of submaximal front-crawl swimming close to maximally allowed during the races substantially increases blood lactate accumulation, i.e., increases the reliance on anaerobic metabolism. Therefore, extended UP is most likely counterproductive for the performance in long-distance swimming, at least for the athletes with a FINA score of <800. On the other hand, the extension of UP could be an effective strategy to train 'lactate tolerance', lactate shuttling, removal, and recycling.
在大多数游泳项目中，水下阶段（UP）对整体游泳表现至关重要。然而，长时间水下阶段的代谢影响仍不清楚。本横断面研究的目的是比较次最大强度自由泳短水下阶段和长水下阶段的血乳酸反应。12名（4名女性）青少年竞技游泳运动员（年龄15.4（1.4）岁）在25米泳池中以预定的“无氧阈”速度进行200米自由泳试验，每次转身时分别采用短（<5米）和长（12.5米）水下阶段，共进行两次。确保两次试验的配速和总时间相同。测量毛细血管血乳酸反应。在另一个时间点进行了<5米和12.5米水下阶段的25米游泳时间测试。当运动员每次从池壁蹬出后采用长水下阶段时，他们运动后的血乳酸浓度达到7.9（2.1）毫摩尔/升，比短水下阶段试验的反应高出两倍多（<0.001）。<5米或12.5米水下阶段的全力25米游泳在运动速度上没有差异（>0.05）。总之，在比赛中接近最大允许时间延长次最大强度自由泳的水下阶段会显著增加血乳酸积累，即增加对无氧代谢的依赖。因此，延长水下阶段至少对FINA得分<800的运动员在长距离游泳中的表现很可能适得其反。另一方面，延长水下阶段可能是训练“乳酸耐受性”、乳酸穿梭、清除和再循环的有效策略。
