Short‐term high‐intensity interval training improves fitness before surgery: A randomized clinical trial

PURPOSE: Improving cardiopulmonary reserve, or peak oxygen consumption([Formula: see text] O(2peak)), may reduce postoperative complications; however, this may be difficult to achieve between diagnosis and surgery. Our primary aim was to assess the efficacy of an approximate 14‐session, preoperative high‐intensity interval training(HIIT) program to increase [Formula: see text] O(2peak) by a clinically relevant 2 ml·kg(−1)·min(−1). Our secondary aim was to document clinical outcomes. METHODOLOGY: In this prospective study, participants aged 45–85 undergoing major abdominal surgery were randomized to standard care or 14 sessions of HIIT over 4 weeks. HIIT sessions involved approximately 30 min of stationary cycling. Interval training alternated 1 min of high (with the goal of reaching 90% max heart rate at least once during the session) and low/moderate‐intensity cycling. Cardiopulmonary exercise testing(CPET) measured the change in [Formula: see text] O(2peak) from baseline to surgery. Clinical outcomes included postoperative complications, length of stay(LOS), and Short Form 36 quality of life questionnaire(SF‐36). RESULTS: Of 63 participants, 46 completed both CPETs and 50 completed clinical follow‐up. There was a significant improvement in the HIIT group's mean ± SD [Formula: see text] O(2peak) (HIIT 2.87 ± 1.94 ml·kg(1)·min(−1) vs standard care 0.15 ± 1.93, with an overall difference of 2.73 ml·kg(1)·min(−1) 95%CI [1.53, 3.93] p < 0.001). There were no statistically significant differences between groups for clinical outcomes, although the observed differences consistently favored the exercise group. This was most notable for total number of complications (0.64 v 1.16 per patient, p = 0.07), SF‐36 physical component score (p = 0.06), and LOS (mean 5.5 v 7.4 days, p = 0.07). CONCLUSIONS: There was a significant improvement in [Formula: see text] O(2peak) with a four‐week preoperative HIIT program. Further appropriately powered work is required to explore the impact of preoperative HIIT on postoperative clinical outcomes.