| 摘要: | The purpose of the study was to investigate the effect of four different intensities of dynamic recovery on post-training blood lactate and heart rate variability in swimmers. Twelve male swimmers from the Kaohsiung County Swimming Team were randomly divided into four groups. Each group participated in one recovery program on four nonconsecutive days in a counterbalanced order. After 100-m front crawl test, the participants received one of the four 20-min recovery program including inactive, low-intensity swimming (best record×165%), moderate-intensity swimming (best record×135% for 10 min, best record×165% for 10 min) and moderate-to-high-intensity swimming (best record×135% for 20 min). Blood samples were collected before and after 100-m front crawl. After 20-min recovery programs, heart rate, heart rate variability data and blood samples were collected at the end of the 1st and 3rd minute. After 1-hour break after recovery programs, the subjects were tested again for their 200-m front crawl time. Repeated-measures one-way ANOVA was used to compare the effects of different recovery programs on blood lactate clearance, heart rate and heart rate variability. The significant level was set at α=.05. The results revealed that 1. No significant difference existed among four recovery programs in blood lactate levels before and after 100-m front crawl (before: inactive: 1.9±0.56, low intensity: 1.8±0.56, moderate intensity: 2.2±0.52. moderate-to-high intensity: 2.0±0.38; after: inactive: 12.2±1.70 mmol•L^(-1), low intensity: 11.5±1.86 mmol•L^(-1), moderate intensity: 11.9±1.77 mmol•L^(-1), moderate-to-high intensity: 11.2±1.87 mmol•L^(-1)). However, the blood lactate was significantly lower after the low-intensity recovery program (1.9±0.49 mmol•L^(-1)) when compared with the other three programs (inactive: 5.0±1.55 mmol•L^(-1), moderate-intensity: 4.0±1.42 mmol•L^(-1), moderate-to-high intensity: 5.0±1.40 mmol•L^(-1), p＜.05). 2. No significant difference in heart rate was found before and after 100-m front crawl. The heart rates after moderate-intensity and moderate-to-high-intensity recovery programs were significantly higher than the other two programs (p＜.05). 3. The performance of the 200-m front crawl after low-intensity recovery program was significantly better than other programs (p＜.05). 4. No significant difference was found in heart rate variability among the recovery programs before swimming; however, participants showed significantly lower low R-R volume, higher high frequency and total power after low intensity-recovery recovery training when compared to other three recovery programs (p＜.05). In conclusion, the low-intensity dynamic recovery may be beneficial for clearance of blood lactate, favorable heart rate variability and better swimming performance. Our results suggest the low-intensity dynamic recovery may recommended for coaches or swimmers when designing recovery training programs. |
