Van Schaardenburgh Michel, Wohlwend Martin, Rognmo Øivind, Mattsson Erney
Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.
J Vasc Surg. 2017 May;65(5):1473-1482. doi: 10.1016/j.jvs.2016.12.106. Epub 2017 Mar 9.
Symptoms of intermittent claudication (IC) are improved by exercise. The improvement might be secondary to increased blood perfusion or increased muscle mitochondrial capacity. Ischemia followed by reperfusion, also named preconditioning, is known to stimulate the mitochondria. We focused on a calf raise exercise inducing preconditioning in the calf muscle of patients with IC. We hypothesized that 8 weeks of this exercise would increase walking performance and mitochondrial capacity without a change in blood flow.
Patients with IC were randomized to either a calf raise exercise group (n = 14) or a traditional walking exercise group (n = 15). The calf raise group was instructed to perform a specific type of calf raise exercise three times a day. The walking group was instructed to walk near the pain threshold at least 30 minutes three times a week. Both interventions lasted 8 weeks and were not supervised. Measurements of walking performance, mitochondrial capacity, peak oxygen uptake, peripheral hemodynamics, and health-related quality of life were obtained on each patient before and after the intervention period. Adherence was measured by a training diary, and an activity monitor was used.
The calf raise group improved pain-free walking distance by 44 meters (P = .04) and maximal walking distance by 99 meters (P = .047). Furthermore, claudication onset time increased by 123 seconds (P = .02), and peak walking time increased by 104 seconds (P = .01). The calf raise group increased the enzyme citrate synthase activity, which is a biomarker of mitochondrial volume-density in the muscle tissue (P = .02). The walking group did not increase any of these variables. Maximal blood flow, peak oxygen uptake, and mitochondrial respiration did not change in any group. The calf raise group experienced less disease anxiety (P < .01). Adherence to the instruction of exercise was 100% in the calf raise group and 80% in the walking group. The calf raise group maintained physical activity. A reduction in activity (P < .01) was found in the walking group.
Calf raise exercise improves walking performance and increases mitochondrial volume-density in the gastrocnemius muscle without increasing blood flow in patients with IC.
间歇性跛行（IC）的症状可通过运动得到改善。这种改善可能继发于血液灌注增加或肌肉线粒体容量增加。缺血再灌注，也称为预处理，已知可刺激线粒体。我们重点关注一种可诱导IC患者小腿肌肉预处理的提踵运动。我们假设，进行8周这种运动会提高步行能力和线粒体容量，而血流量不变。
IC患者被随机分为提踵运动组（n = 14）或传统步行运动组（n = 15）。提踵组被指导每天进行特定类型的提踵运动3次。步行组被指导在疼痛阈值附近行走，每周至少3次，每次至少30分钟。两种干预均持续8周，且无监督。在干预期前后，对每位患者进行步行能力、线粒体容量、峰值摄氧量、外周血流动力学及健康相关生活质量的测量。通过训练日记测量依从性，并使用活动监测器。
提踵组无痛步行距离增加了44米（P = 0.04），最大步行距离增加了99米（P = 0.047）。此外，跛行发作时间增加了123秒（P = 0.02），峰值步行时间增加了104秒（P = 0.01）。提踵组肌肉组织中线粒体体积密度的生物标志物柠檬酸合酶活性增加（P = 0.02）。步行组这些变量均未增加。任何一组的最大血流量、峰值摄氧量和线粒体呼吸均未改变。提踵组疾病焦虑感较轻（P < 0.01）。提踵组对运动指导的依从率为100%，步行组为80%。提踵组保持了身体活动。步行组活动量减少（P < 0.01）。
提踵运动可改善IC患者的步行能力，增加腓肠肌线粒体体积密度，且不增加血流量。
