Introduction
Breast cancer (BC) is a malignant cancer that severely harms women’s health worldwide and is the most common cancer in women in both developed and developing countries. In developing countries, the incidence of BC is rising due to increased life expectancy, the expansion of urbanization, and the adoption of a western lifestyle [
1]. The most common manifestations in postoperative BC patients are mental fatigue, anxiety, and depression [
2‐
4]. Moreover, the physical inactivity due to weakness and upper extremity function limitation after surgery may cause the decrease in muscle strength and cardiorespiratory endurance, and then seriously affect the mood and QOL of BC patients [
5,
6].
Some results of previous studies demonstrated that exercises may improve muscle strength and cardiorespiratory endurance in BC patients during rehabilitation and further improve their emotions and QOL [
5,
7‐
12]. However, there are some problems in the current exercise rehabilitation forms. First, patients are usually unable to adhere to regular group exercise rehabilitation in hospital outpatient clinics or fitness centers due to the traffic delays or personal schedules; second, although face-to-face private exercise guidance may have a better rehabilitation effect, it will increase the economic burden of patients.
With the universalization and extensive applications of the internet, exercise intervention and guidance for BC patients via phone social media apps and remote video have become possible. Related studies have been carried out [
13‐
15]. However such studies have some deficiencies such as a singular method of exercise intervention and exercise guidance [
16‐
19]. Therefore, due to the limitations of previous studies, we aimed to investigate the effects of the CEIBISMS on QOL, muscle strength and cardiorespiratory capacity in postoperative BC patients in China.
Discussion
The aim of this study was to estimate the effects of the CEIBISMS on the QOL, muscle strength and cardiorespiratory capacity in postoperative BC patients with BC in China. In the present study, according to the changes of SF-36, SPSDCT, ALT and VO2max at baseline as well as at 12 weeks after the combined exercise intervention, we demonstrated that the CEIBISMS resulted in a statistically significant improvement in many subdomains of the SF-36, SPSDCT and ALT, which in turn was associated with improvements in QOL, muscle strength. The intervention group had significant improvement in VO2max compared with the control group. The CEIBISMS had a effect of improving cardiorespiratory in postoperative patients with BC in China.
The SF-36 can be applied to assess the QOL of BC patients [
26‐
29]. Previous studies have shown that physical exercise management can significantly improve the QOL of BC patients [
13,
30,
31]. However, few clinical trials have verified whether diversified exercise interventions have an increased beneficial effect on the QOL of BC patients. According to our research results, after 12 weeks of exercise intervention, the indexes of “vitality”, “mental health”, and “reported health transition” in SF-36 improved in the intervention group compared with the control group, with significant differences between the groups. The enhancement in vitality suggested that internet-based diversified exercise interventions can improve the subjective perception of BC patients toward vitality and fatigue. Since the sense of fatigue is common among postoperative survivors of BC [
32,
33], the improvement of vitality has important implications for the enhancement of their QOL [
34‐
36]. Patients with BC usually have psychosocial problems due to illness and disability caused by the surgery [
37,
38]. The results of the research on the index of mental health indicated that internet-based diversified exercise interventions can improve the psychological aspects of BC patients. The results of reported health transition revealed that the overall health status of the subjects improved after 12 weeks of intervention. The indexes of “role-physical” and “general health” in the SF-36, after 12 weeks of exercise intervention, although without significant difference between the groups, showed an increase within the intervention group. The results of the role-physical indicated that BC survivors in the intervention group achieved some improvement in their functional limitations caused by their physiological health problems. The results of general health showed that BC survivors in the intervention group improved their own health status and its development trends. In conclusion, judging from the results of the study, 12-week of the CEIBISMS improved the QOL of postoperative BC patients.
SPSDCT and ALT can reflect the muscle strength of lower and upper extremities. After 12 weeks of diversified exercise interventions, the intervention group showed significant improvement compared with the control group. These improvements illustrated that the CEIBISMS can promote the development of muscle strength in BC patients. When arm curl test was performed, only the non-affected arm was tested in consideration that the subjects may refuse to complete the test for fear of causing or aggravating lymphedema of the affected limb. However, when the intervention was conducted, the bilateral arms were rehabilitated together. Therefore, the enhancement of the strength of the non-affected arm muscle strength can be used to speculate the improvement of muscle strength in the affected arm. In addition, there were no side effects that caused or aggravated lymphedema during the intervention, which also confirmed the conclusions of previous studies that resistance training does not cause or aggravate lymphedema in the affected side of BC survivors [
39‐
43].
In previous studies, approximately 85% of women diagnosed with BC for the first time were over the age of 50, so the majority of survivors of BC were older women [
44]. The improvement of muscle strength can promote balance control ability [
45,
46] effectively preventing falls. Falls among the elderly are a major risk. Among the many factors causing falls of the elderly, muscle weakness is the main one [
47]. In addition to causing falls, muscle weakness can trigger other diseases, especially the limitation of physical function or even loss of self-care ability [
48‐
50]. Therefore muscle strength is of essential importance for postoperative survivors of BC. As suggested in the research results, internet-based diversified exercise interventions can reduce the risk of falling and future diseases of BC survivors by improving muscle strength.
It has been reported that about 60% BC survivors suffered from significant decrease in muscle strength of their upper limbs after surgery, seriously affecting the daily life of BC patients, thereby reducing their QOL [
51]. Therefore, the improvement of muscle strength may have a positive effect on improving their QOL [
52,
53]. As manifested in the research results, the improvement of QOL of BC survivors, to some extent, can be attributed to the improvement of muscle strength of the upper limbs.
Cardiorespiratory capacity was assessed by estimating the VO2max of each participant [
54]. In previous studies it was reported that the improvement of cardiorespiratory endurance is positively correlated with the reduction of mortality in cancer patients [
55,
56], showing the importance of cardiorespiratory for BC patients [
57,
58]. The results of this study revealed that, after 12 weeks of intervention, although the difference regarding the VO2max between the intervention group and the control group showed no statistical significance, there was a trend of improvement in the intervention group through comparison within the group. Our training method for cardiorespiratory endurance was to let the subjects walk within a specified time to finish certain number of steps, but this exercise method, compared with cycle ergometer exercise [
59,
60], had a difficulty in controlling exercise intensity, which may affect further improvement of cardiorespiratory endurance of the subjects. After a short-term intervention of 12 weeks, there was a trend of improvement in cardiorespiratory endurance of subjects in the intervention group. If medical supervision is further strengthened in cardiorespiratory endurance training and the intervention period is extended, better outcome would be expected.
No follow-up after study was the limitation of this study. In addition, the study period may have been too short to see the full benefits of the CEIBISMS on the improvement of QOL and cardiorespiratory capacity. We should do follow-up after the study and increase the intervention time in the future study.
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