Does surgery improve aerobic performance?

This study evaluated whether surgery has an effect on aerobic performance in colorectal cancer patients. 

Patients with colorectal cancer may suffer from reduced lean body mass (calculated by subtracting body fat weight from total body weight) that cannot be reversed nutritionally, a condition referred to as cachexia. People with enough lean body mass have the ability to better utilize oxygen in the production of energy (aerobic metabolism), other than breaking down fats in the absence of oxygen, which is known as anaerobic metabolism. Such people are said to have high oxygen performance. Thus, they don't suffer from low anaerobic threshold or AT (defined as reaching the point where lactic acid begins to accumulate in the bloodstream) which can, in time, lead to death. Surgery is thought to have ability to restore the patient's lean body mass which, in turn, increases the AT, resulting in high oxygen performance. This study aims to investigate the effectiveness of surgery in improving aerobic performance in colorectal cancer patients. 

The study involved 60 participants. Of these, 30 patients were diagnosed with colorectal cancer (the study group) and the other 30 did not have colorectal cancer, but they were a match of the colorectal cancer patients (the control group). At the beginning of the study, before surgery, the AT for study group was 14.40 ml kg^-1 min^-1, while that of the control group was 19.67 ml kg^-1 min^-1.

After 10 months following surgery, the AT for the study group has increased by 2.6 ml kg^-1 min^-1 to 17.00 ml kg^-1 min^-1, which was rising towards the AT of the control group.

In summary, surgery was able to improve aerobic performance in colorectal cancer patients.

The study involved a very small number of patients. Future studies on larger populations are expected in order to confirm these results.