Gymnastik- och idrottshögskolan, GIH

PURPOSE: Following colorectal cancer diagnosis and anti-cancer therapy, declines in cardiorespiratory fitness and body composition lead to significant increases in morbidity and mortality. There is increasing interest within the field of exercise oncology surrounding potential strategies to remediate these adverse outcomes. This study compared 4 weeks of moderate-intensity exercise (MIE) and high-intensity exercise (HIE) training on peak oxygen consumption (V̇O2peak) and body composition in colorectal cancer survivors.

METHODS: Forty seven post-treatment colorectal cancer survivors (HIE = 27 months post-treatment; MIE = 38 months post-treatment) were randomised to either HIE [85-95 % peak heart rate (HRpeak)] or MIE (70 % HRpeak) in equivalence with current physical activity guidelines and completed 12 training sessions over 4 weeks.

RESULTS: HIE was superior to MIE in improving absolute (p = 0.016) and relative (p = 0.021) V̇O2peak. Absolute (+0.28 L.min(-1), p < 0.001) and relative (+3.5 ml.kg(-1).min(-1), p < 0.001) V̇O2 peak were increased in the HIE group but not the MIE group following training. HIE led to significant increases in lean mass (+0.72 kg, p = 0.002) and decreases in fat mass (-0.74 kg, p < 0.001) and fat percentage (-1.0 %, p < 0.001), whereas no changes were observed for the MIE group. There were no severe adverse events.

CONCLUSIONS: In response to short-term training, HIE is a safe, feasible and efficacious intervention that offers clinically meaningful improvements in cardiorespiratory fitness and body composition for colorectal cancer survivors.

IMPLICATIONS FOR CANCER SURVIVORS: HIE appears to offer superior improvements in cardiorespiratory fitness and body composition in comparison to current physical activity recommendations for colorectal cancer survivors and therefore may be an effective clinical utility following treatment.

PURPOSE: Whether the benefits of exercise during chemotherapy continue into survivorship is not well-known. Here, the aim was to examine the effects of two exercise interventions on self-reported health-related and objectively measured physiological outcomes 12 months following commencement of chemotherapy.

METHODS: Two hundred and forty women with breast cancer stage I-IIIa were randomized to 16 weeks of high-intensity aerobic interval training combined with either resistance training (RT-HIIT), or moderate-intensity aerobic training (AT-HIIT), or to usual care (UC).

PRIMARY OUTCOME: cancer-related fatigue (CRF); secondary outcomes: quality of life (QoL), symptom burden, muscle strength, cardiorespiratory-fitness, body mass, and return to work.

RESULTS: Compared to UC, both RT-HIIT and AT-HIIT significantly counteracted increases in total CRF (ES = - 0.34; ES = - 0.10), daily life CRF (ES=-0.76; ES=-0.50, and affective CRF (ES=-0.60; ES=-0.39). Both RT-HIIT and AT-HIIT reported significantly lower total symptoms (ES = - 0.46, ES = - 0.46), and displayed gains in lower limb (ES = 0.73; ES = 1.03) and handgrip muscle strength (surgery side ES = 0.70, ES = 0.71; non-surgery side ES = 0.57, ES = 0.59). AT-HIIT displayed significant reductions in body mass (ES = - 0.24), improved QoL: role (ES = 0.33) and emotional functioning (ES = 0.40), and a larger proportion had returned to work (p = 0.02) vs UC.

CONCLUSION: These findings emphasize the beneficial effects of supervised high-intensity exercise during chemotherapy to improve the health and to reduce societal costs associated with prolonged sick leave for patients with breast cancer several months following chemotherapy.

IMPLICATIONS FOR CANCER SURVIVORS: These findings provide important information with substantial positive consequences for breast cancer survivorship. High-intensity exercise programs during chemotherapy and support to maintain physical activity can be a powerful strategy to manage or prevent many of the short- and long-term adverse effects of treatment for the increasing cohort of cancer survivors.