Lindsay Angus, Petersen Carl, Blackwell Gavin, Ferguson Hamish, Parker Greg, Steyn Nina, Gieseg Steven P
School of Health Sciences, University of Canterbury, Christchurch, New Zealand.
Program in Physical Therapy and Rehabilitation Sciences, University of Minnesota, Minneapolis, USA.
BMJ Open Sport Exerc Med. 2017 May 31;3(1):e000229. doi: 10.1136/bmjsem-2017-000229. eCollection 2017.
Coaches continually seek new ways of doing things and also refine existing techniques to improve sporting performance. Coaches are currently experimenting using ischaemic preconditioning (IPC) over consecutive days in the hope of improving competitive performances.
First, to quantify the physiological impact of 1 week of IPC on simulated Keirin cycling performance. Second, to investigate if biochemical stress markers are affected over the treatment period.
Using a randomised, sham-controlled design, 18 active adults undertook seven consecutive days of IPC treatment (4×5 min occlusion/reperfusion) applied to each leg at either 220 mm Hg (treatment, n=9) or 20 mm Hg (sham, n=9). Urinary measures of inflammation, oxidative stress and indirect nitric oxide synthesis were undertaken daily. A simulated Keirin cycling competition (4×30 s Wingate tests) was performed on day 10, with baseline and postintervention cycling VO2max (days 1, 11 and 18) and 30 s Wingate tests (day 2) undertaken for comparison.
The treatment group had enhanced mean cycling power (3.4%), while neopterin and biopterin in conjunction with total neopterin were significantly lower (p<0.05) and total biopterin significantly greater (p<0.05) during the simulated Keirin. Aerobic fitness measures significantly improved from baseline to postintervention (VO2peak: 12.8% ↑, maximal aerobic power: 18.5% ↑).
Seven consecutive days of IPC improved aerobic and anaerobic capacity measures, with modulations in oxidative stress, immune system activation and nitric oxide/catecholamine synthesis.
教练们不断寻求新的训练方法,同时也在改进现有技术以提高运动成绩。目前,教练们正在尝试连续多日使用缺血预处理(IPC),以期提升竞技表现。
其一,量化为期1周的IPC对场地自行车赛模拟成绩的生理影响。其二,研究在治疗期间生化应激标志物是否受到影响。
采用随机、假手术对照设计,18名活跃的成年人连续7天接受IPC治疗(4×5分钟阻断/再灌注),施加于每侧腿部的压力分别为220毫米汞柱(治疗组,n = 9)或20毫米汞柱(假手术组,n = 9)。每天进行尿液炎症、氧化应激和间接一氧化氮合成指标的检测。在第10天进行场地自行车赛模拟比赛(4×30秒温盖特测试),并在第1天、第11天和第18天进行基线和干预后自行车运动最大摄氧量测试,以及在第2天进行30秒温盖特测试,以便进行比较。
治疗组的平均骑行功率提高了3.4%,在模拟场地自行车赛期间,新蝶呤和生物蝶呤与总新蝶呤显著降低(p<0.05),总生物蝶呤显著升高(p<0.05)。有氧适能指标从基线到干预后有显著改善(峰值摄氧量:升高12.8%,最大有氧功率:升高18.5%)。
连续7天的IPC改善了有氧和无氧能力指标,同时对氧化应激、免疫系统激活以及一氧化氮/儿茶酚胺合成产生了调节作用。