Two-year follow-up after a six-week high-intensity training intervention study with breast cancer patients: physiological, psychological and immunological differences.

PURPOSE Previously we demonstrated the feasibility of a six-week-long combination of high-intensity interval endurance and strength training (HIT/HIRT) for women with nonmetastatic breast cancer leading to improvements in psychological well-being and performance. Now we report results of a 24-month follow-up. METHODS Previous intervention (IG, n = 10; 58.7 ± 8.4yrs) and control group (CG, n = 9; 58.8 ± 6.6yrs) were asked for follow-up examinations 12 (T12) and 24 months (T24) after cessation of the supervised training (POST). Medical history, mental well-being, performance and immunological variables were analyzed with respect to intervention start (PRE). RESULTS IG maximum oxygen consumption (⩒O2peak) 12%-improved POST (p = 0.05) and declined to baseline values T24, while CG ⩒O2peak increased 12% T24 (p = 0.01). IG strength (1RM) increased 31% POST (p < 0.001) and remained above baseline level T24 (p = 0.003), whereas CG 1RM slightly improved T24 (+19%, p = 0.034). IG Anxiety and Depression decreased POST and did not change until T24. IG C-reactive protein decreased POST and increased to pre-exercise levels T24. CG immunological/inflammatory/life quality markers did not change. CONCLUSIONS Six weeks of HIT/HIRT by breast cancer patients can induce similar beneficial effects like two years of convalescence, but outcomes were unstable and showed a fast backslide in aerobic capacity, activity level and in pro-inflammatory state within 12 months.IMPLICATIONS FOR REHABILITATIONHigh-intensity interval endurance and strength training (HIT/HIRT) for female breast cancer patients was shown to improve psychological well-being and performance, but long-term effects/adherence are unknown.Significant backslides in aerobic capacity, activity level as well as in the pro-inflammatory response after one and two years are observed and should be monitored.Continuous supervision and/or support of breast cancer patients before, during, and after medical care due to poor training adherence when voluntarily executed is recommended.