In medical studies, the efficacy of medical treatments (called interventions) is evaluated within a group of study participants. You will be given a sentence of a study report in which your task is to list the phrases that describe the intervention(s) of the study. You should list the phrase in the same order that they appear in the text, separated by commas. If no information about the interventions is mentioned, just answer with "not found". Interventions are: a specific drug, surgery, talking therapy, a lifestyle modification, control or placebo treatment. Do not include details, dosages, frequency and duration, intervention mentions that are not in an informative span of text.

Example Input: The 2 groups were comparable in terms of age , sex , symptoms and ipsilateral glomerular filtration rate .
Example Output: not found

Example Input: To study the effects of physical exercise on biochemical risk factors for ischaemic heart disease 31 healthy middle aged men undertook regular physical exercise for two months and 29 served as controls in a randomised trial .
Example Output: physical exercise

Example Input: Since the results were essentially identical between the techniques , it seems that comparable pathophysiological factors affect TLCO during breath holding and constant exhalation .
Example Output:
breath holding, constant exhalation