Heat therapy vs. supervised exercise therapy for peripheral arterial disease: a 12-wk randomized, controlled trial

Am J Physiol Heart Circ Physiol. 2019 Jun 1;316(6):H1495-H1506. doi: 10.1152/ajpheart.00151.2019. Epub 2019 Apr 19.

Abstract

Peripheral arterial disease (PAD) is characterized by lower limb atherosclerosis impairing blood supply and causing walking-induced leg pain or claudication. Adherence to traditional exercise training programs is poor due to these symptoms despite exercise being a mainstay of conservative treatment. Heat therapy improves many cardiovascular health outcomes, so this study tested if this was a viable alternative cardiovascular therapy for PAD patients. Volunteers with PAD were randomized to 12 wk of heat (n = 11; mean age 76 ± 8 yr, BMI 28.7 ± 3.5 kg/m2, 4 females) or exercise (n = 11; 74 ± 10 yr, 28.5 ± 6.8 kg/m2, 3 females). Heat involved spa bathing at ∼39°C, 3-5 days/wk for ≤30 min, followed by ≤30 min of callisthenics. Exercise involved ≤90 min of supervised walking and gym-based exercise, 1-2 days/wk. Following the interventions, total walking distance during a 6-min walk test increased (from ∼350 m) by 41 m (95% CI: [13, 69], P = 0.006) regardless of group, and pain-free walking distance increased (from ∼170 m) by 43 m ([22, 63], P < 0.001). Systolic blood pressure was reduced more following heat (-7 mmHg, [-4, -10], P < 0.001) than following exercise (-3 mmHg, [0, -6], P = 0.078), and diastolic and mean arterial pressure decreased by 4 mmHg in both groups (P = 0.002). There were no significant changes in blood volume, ankle-brachial index, or measures of vascular health. There were no differences in the improvement in functional or blood pressure outcomes between heat and exercise in individuals with PAD. NEW & NOTEWORTHY Heat therapy via hot-water immersion and supervised exercise both improved walking distance and resting blood pressure in peripheral arterial disease (PAD) patients over 12 wk. Adherence to heat therapy was excellent, and the heat intervention was well tolerated. The results of the current study indicate that heat therapy can improve functional ability and has potential as an effective cardiovascular conditioning tool for individuals with PAD.

Keywords: claudication; elderly; hot-water immersion; passive heat; peripheral arterial disease; peripheral vascular disease; walking distance.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Blood Pressure
  • Exercise Therapy*
  • Exercise Tolerance
  • Female
  • Hot Temperature*
  • Humans
  • Hydrotherapy*
  • Male
  • Middle Aged
  • New Zealand
  • Peripheral Arterial Disease / diagnosis
  • Peripheral Arterial Disease / physiopathology
  • Peripheral Arterial Disease / therapy*
  • Quality of Life
  • Recovery of Function
  • Time Factors
  • Treatment Outcome
  • Walking