Comparison of respiratory muscle strength and endurance, maximal oxygen consumption, and fatigue in colorectal cancer survivors with healthy adults.

ABSTRACT

PURPOSE: This study aimed to evaluate respiratory muscle strength and endurance, maximal oxygen consumption, and fatigue of colorectal cancer (CRC) survivors and compare them with healthy individuals. METHODS: Demographic and clinical characteristics were recorded. Respiratory muscle strength (maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP)) was measured using an electronic mouth pressure device, and respiratory muscle endurance was assessed using a constant workload protocol with linear workload device. Peak oxygen consumption (VO2peak) was measured using the cardiopulmonary exercise test (CPET) with modified Bruce protocol. Fatigue was assessed using the Brief Fatigue Inventory (BFI). RESULTS: The patients had similar demographic characteristics (p > 0.05). MEP (cmH2O and %predicted) were lower in the CRC group than in healthy controls (p < 0.05). MIP (cmH2O and %predicted) and test duration did not differ between the groups (p > 0.05). VO2peak (ml/min and %predicted) and VO2peak/kg (%predicted) were significantly lower in the CRC group (p < 0.05). BFI score differed significantly in the CRC and control groups (p < 0.05). CONCLUSION: Respiratory muscle strength, maximal exercise capacity, and fatigue are adversely affected in CRC survivors. Cancer treatment may cause loss of muscle strength and impair energy metabolism and oxygen transmission. These changes can result in decreased exercise capacity and respiratory muscle strength and increased fatigue. Studies examining the effects of different exercise training programs in CRC survivors are needed.