Breast cancer is the most common and emotionally traumatic type of cancer among women (
1-
3). More than 120,000 women in the UK and more than 40,000 women in the United States die from breast cancer every year. In Iran, breast cancer accounts for 25% of all cancers and is the most common cancer among women (
3).
Numerous studies have shown that metabolic dysfunction, hormones, and inflammatory mechanisms affect the progression of breast cancer (
4-
7). Evidence suggests that stressors in various forms can trigger physical stimulation and changes in the immune system (
8). Epidemiological studies have shown a connection between obesity and increased risk of developing different subtypes of breast cancer, including triple-negative breast cancer, a particularly aggressive form of breast cancer with poor outcome and few therapeutic options (
8).
Depression and sleep disturbance occur in patients with breast cancer; 20% to 30% of breast cancer patients suffer from depression and anxiety, due to the negative consequences of a cancer diagnosis and the sequelae of cancer-related treatments (
9). Also, chemotherapy followed by breast cancer can have a major impact on patients’ quality of life, disrupting their physical, mental, social and spiritual well-being, and in other words, reducing their quality of life indicators (
10). The depression and anxiety symptoms can persist for several years, leading to adverse effects on the patient’s quality of life, compliance to medical treatment, recurrence, survival and also recovery from surgery during hospital stay (
11). Metastatic breast cancer and its treatment have a major impact on the survivor’s quality of life (
8-
11). Following a diagnosis of breast cancer, an assessment of QOL is an important clinical outcome measure, because patients have to face major stressors that are likely to deteriorate their QOL, not only just after diagnosis but also in the long term (e.g., facing a life-threatening illness, painful and impairing treatments, significant role changes, and issues about body image) (
8-
11).
Exercise therapy has been studied in a variety of populations with cancer to counteract the side effects of treatments (
12). Concurrent endurance and strength training are particularly relevant to improving overall health as they combine the benefits of each single exercise modality to bring about local. Therefore, aerobic resistance training is more effective than aerobic exercise in improving body composition, quality of life, and cardiovascular strength and fitness (
12).
Hojan et al. (
13) showed that mixed type physical activity (aerobic training, AT, and resistance training, RT) during endocrine therapy for breast cancer could prevent negative changes of the treatments, in body build in premenopausal women. Battaglini et al. (
14) suggest that exercise with an emphasis on resistance training promotes positive changes in body composition and strength in breast cancer patients undergoing treatment. Sprod et al. (
15) showed that four weeks of moderate home-based aerobic exercise and resistance training can be helpful for patients with breast cancer under radiotherapy and sleep quality was higher in the training group but not significantly different. Ohira et al. (
16) showed that QOL scores improved in the training group after 6-months of weight-loss training in women who survived from breast cancer, however, the previous research literature on the effects of this type of exercise training on body composition improvement and quality of life indicators in postmenopausal women with cancer is limited.