Author(s): DAUBRAH-SCOTT, T., FRADELY, W., WALL, J.J., JONES, E., WILKINSON, D.J., SMITH, K., ATHERTON, P.J., LUND, J., PHILLIPS, B.E. , Institution: UNIVERISTY OF NOTTINGHAM, Country: UNITED KINGDOM, Abstract-ID: 2694

INTRODUCTION:
Exercise prehabilitation is being increasingly adopted to enhance physiological resilience before elective surgery, and therefore, post-operative outcomes. In the UK, cancer pathways dictate that the window for prehabilitation is <31 days (d) due to mandated clinical timeframes. High-intensity interval training (HIIT) has been widely studied as a time-efficient strategy to improve pre-surgical health. However, in [colorectal] cancer (CRC) patients, short-term HIIT-alone may not induce improvements in muscle mass – a key biomarker of physiological resilience. We investigated if the addition of resistance exercise to HIIT (ReHIIT) enhances adaptation compared to HIIT-alone, in CRC patients.
METHODS:
CRC patients (n=41, 21M/20F; 62.9+/-8.5 y) scheduled for resection with curative intent were recruited into a single-centre randomised trial. Patients were allocated to HIIT or ReHIIT for ~31 d during the window between decision-to-treat and surgery. Assessments were conducted at baseline (V1), pre-surgery (V2), and 6-weeks post-surgery (V3). Outcomes were lower-limb strength (1-RM leg press and extension), handgrip strength, 6-minute walk test distance, timed up-and-go, short physical performance battery (SPPB), body composition (DXA), vastus lateralis architecture (ultrasound), and cardiorespiratory fitness (CRF; cardiopulmonary exercise testing (CPET)). Data were analysed by 2-way ANOVA (group x time) with significance set at p<0.05.
RESULTS:
Lower-limb strength increased in ReHIIT from V1 to V2 (n=41; leg extension: Δ+17.6±4.6kg; leg press: Δ+22.7±4.2kg; p<0.05) returning to baseline post-operatively (V2–V3; p<0.05), with no significant change observed in HIIT. VO2PEAK increased in both groups from V1 to V2 (n=28; HIIT: Δ+0.16±0.04L/min; ReHIIT: Δ+0.10±0.03L/min; p<0.05), before declining from V2 to V3 to baseline levels (p<0.05). Vastus lateralis ultrasound cross-sectional area increased from V1 to V2 in HIIT (n=28; p<0.05), with a non-significant decrease in ReHIIT. No significant changes were observed in handgrip strength, 6-minute walk distance, time up-and-go, or SPPB. Body fat % (n=41) decreased only in ReHIIT from V1 to V2 (Δ-0.22±0.32%; p<0.05) with a further non-significant reduction post-surgery (p=0.08). Bodyweight (n=41) decreased from V1 to V3 in both groups (HIIT: Δ-2.7±1.3kg; ReHIIT: Δ-2.7±0.8kg; p<0.05).
CONCLUSION:
Adding resistance exercise to HIIT during rapid prehabilitation elicited greater improvements in lower-limb strength, while both interventions improved CRF. However, these gains were not consistently reflected in functional outcomes and were attenuated post-surgery. Multimodal prehabilitation may provide a stronger stimulus than unimodal, although optimisation is needed to translate this into improved, sustained functional outcomes.