Can a short workout before breast cancer surgery change tumor markers?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Newly diagnosed, histologically confirmed stage I-III breast cancer * Planning to undergo definitive surgical management with lumpectomy or mastectomy with in the next 8 weeks. * Willing and able to participate in the intervention for at least 3 weeks prior to surgery. * ECOG performance status of 0 or 1 * Approval by oncologist or surgeon * Willingness to be randomized. * English speaking and able to read English Exclusion Criteria: * Concurrent other malignancy or history of other malignancy treated within the past 3 years (other than non-melanoma skin cancer or in situ cervical cancer) * Presence of metastatic disease * Scheduled to receive any form of neoadjuvant cancer therapy * Locally advanced breast cancer not amenable to primary surgery * History of prior ipsilateral breast cancer * Taking tamoxifen, raloxifene or an aromatase inhibitor at the time of breast cancer diagnosis * Absolute contraindications to maximal exercise testing as recommended by the American Thoracic Society * Any condition which in the investigator's opinion makes the subject unsuitable for study participation * Participating in another clinical study with competing study outcomes * Pregnant (i.e., positive beta-HCG) or breast feeding * Unable to comply with protocol and/or not available for follow-up assessments * Participation in more than 90 minutes a week of moderate-intensity recreational activity (not including activities such as gardening, bowling, golfing with a cart) as assessed by the Leisure Score Index of Godin Leisure- Time Exercise Questionnaire (LSI) (Appendix I) or recent participation (past 6 months) in two or more strength training sessions per week. * Diabetes mellitus requiring insulin or oral agents; patients with diet-controlled diabetes will be allowed to participate