Summary
Introduction: Cancer is one of the leading causes of death worldwide. However, if diagnosed in an operable stage, it is treated as a chronic disease. As such, long-term results and quality of life requirements imposed a comprehensive approach. Prehabilitation programs encompassing nutritional, physical, and psychological components improved the recovery and minimized the complication rate after surgery. We will focus on physiotherapy as part of prehabilitation in this review.
Methods: For systematic search, we used the MEDLINE/PubMed (National Library of medicine), Cochrane Central Register of Controlled Trials (Wiley), Embase (Elsevier, Web of Science, and Cochrane database of systematic reviews. The last search update was on 15th December 2020. The search included randomized clinical trials or quasi-randomized clinical trials evaluating exercise or other non-pharmacological preoperative interventions in gastrointestinal cancers.
Results: The ten trials included 1058 patients, 535 (50,6%) patients were in the experimental group, and 523 (49,4%) patients were in the control group. Bicycle exercise training was the best-ranked intervention with the standard mean difference (SMD) of 1,4077 (95% C.I. is 0,7018 – 2,1135) to improve vital functional capacity (s, VO˙ 2 at uˆ L). Short-term exercise affected inspiratory muscle strength, and SMD was 1,1819 (95% C.I.,2953 – 2,0684). Short- term intensity training program SMD was 0,8356 (95% C.I. 0,2042 - 1,4669), and short- term intensity program for muscle endurance 0,8156 (95% C.I. 0,2042 – 1,4669). improves respiratory muscle endurance. Small effect was shown on quality of life in high-intensity cycling interval training SMD 0,7439( 95%C.. 0,0856 – 1,4023), WHO performance status in bicycle exercise training SMD 0,7068( 95% C.I. 0,0547 – 1,3589), mean number of complication in high-intensity endurance training SMD 0,3606 (95% C.I. 0,0072 – 0,7141). Conclusion: Although exercise therapy has been shown to improve vital capacity and respiratory muscle strength, there was a lack of comparison between different exercises. Evidence from these indirect-comparisons studies indicated that physical activity should be encouraged during the preoperative period before oncologic surgery.

Relevance
This systematic review has shown that exercise therapy is essential for enhancing respiratory muscle strength and vital capacity, as this comprehensive study has demonstrated. These indirect comparison studies provided evidence that preoperative physical exercise before oncologic surgery should be recommended. Pulmonary cancer and other pulmonary diseases should be treated with physical activity and physiotherapy.