Chemo Brain Prehab Project

Inclusion Criteria: * Individuals with stage II or III colorectal cancer undergoing chemotherapy with fluorouracil, capecitabine, or oxaliplatin. * Aged 60-85 years old. * Fluent in English * Male and female participants * Not engaged in structured exercise training\* within the six months before providing consent. Exclusion Criteria: * Presence of comorbidities that may significantly alter the metabolic response to exercise (e.g., diabetes mellitus). * Any contraindication to the multivitamin supplementation (Forceval), including known hypercalcaemia, haemochromatosis, peanut or soya allergy, current use of phenytoin or tetracycline antibiotics, and clinically significant impaired renal or hepatic function. * Evidence of pre-existing cognitive impairment, including diagnosis of dementia, other neurodegenerative disorders (e.g., Alzheimer's disease), or clinically indicated mild cognitive impairment. * Diagnosis of atrial fibrillation and haematological malignancy. * Participants without home internet access will be excluded due to the online delivery of the exercise programme. * Diagnosis of profound hearing loss. * Receiving palliative care. * Presence of synchronous cancer. * Structured exercise refers to planned and organised physical activity, such as gym workouts, exercise classes or a team sport, which are designed to improve or maintain physical fitness, often with instruction, rules, and goals.