Exercise intensity prescription in cancer survivors: ventilatory and lactate thresholds are useful submaximal alternatives to VO 2peak .

PURPOSE: Most studies with cancer survivors use percentages of peak oxygen uptake (VO2peak ) for intensity prescription. Lactate or ventilatory thresholds might be useful submaximal alternatives, but this has never been investigated. Therefore, we aimed at comparing three training sessions prescribed using %VO2peak (reference), lactate thresholds, and ventilatory thresholds in terms of meeting the vigorous-intensity zone, physiological, and psychological responses.

METHODS: Twenty breast (58 ± 10 years) and 20 prostate cancer survivors (68 ± 6 years), 3.6 ± 2.4 months after primary therapy, completed a maximal cardiopulmonary exercise test and three vigorous training sessions in randomized order: 38 min of cycling at 70% VO2peak (M-VO2peak ), 97% of individual anaerobic lactate threshold (M-IAT), and 67% between ventilatory thresholds 1 and 2 (M-VT). Heart rate (HR), blood lactate concentration (bLa), perceived exertion, and enjoyment were assessed.

RESULTS: Cancer survivors exercised at 75 ± 23, 85 ± 18, and 79 ± 19 W during M-VO2peak , M-IAT, and M-VT (p > .05). Sessions could not be completed in 3, 8, and 6 cases. Session completers showed HR of 82 ± 7, 83 ± 9, and 84 ± 8 %HRpeak and bLa of 3.7 ± 1.9, 3.9 ± 0.9, and 3.9 ± 1.5 mmol·l-1 , which was not different between sessions (p > .05). However, variance in bLa was lower in M-IAT compared to M-VO2peak (p = .001) and to M-VT (p = .022).

CONCLUSION: All intensity prescription methods on average met the targeted intensity zone. Metabolic response was most homogeneous when using lactate thresholds.

IMPLICATIONS FOR CANCER SURVIVORS: Submaximal thresholds are at least as useful as VO2peak for intensity prescription in cancer survivors. Overall, slightly lower percentages should be chosen to improve durability of the training sessions.