Breast cancer (CA) is the most common malignant disease affecting women of all ages [
To manage the side effects of conventional cancer treatments and restore physical functioning and QOL, many female breast cancer survivors turn to complementary therapies such as Tai Chi and Qigong [
Tai Chi (TC) Qigong, a mind-body exercise, was developed in China in the late 1970s and has gained popularity in both Eastern and Western countries [
The objectives of this study were (1) to compare the shoulder mobility and muscular strength among breast CA survivors with and without TC Qigong training with that of healthy individuals, (2) to compare the QOL of breast CA survivors with and without TC Qigong training, and (3) to explore the associations between shoulder impairments and QOL in breast CA survivors with regular TC Qigong training.
Previous studies have shown that breast CA patients or survivors who exercise regularly have greater shoulder mobility and muscular strength when compared to control participants [
Eleven women who had recovered from breast CA and received TC Qigong training at the Hong Kong Wushu and Art Service Centre, which provides TC Qigong training classes for cancer survivors, were recruited (TC Qigong CA group). In addition, age- and sex-matched control participants both with (CA-control group,
Individuals were excluded if they met any of the following criteria: (1) having significant neurological, musculoskeletal (e.g., history of shoulder dislocation or frozen shoulder), cardiovascular, peripheral vascular, or kidney disorders; (2) being receiving chemotherapy/radiotherapy, anti-cancer medication, acupuncture, or other cancer treatments; (3) having recurrent breast CA or cancer spread to other organs; (4) being exercising regularly; (5) having a smoking habit; (6) having received a lumpectomy instead of a mastectomy; or (7) being pregnant. The participants in the healthy-control group fulfilled the same aforementioned inclusion and exclusion criteria with the exceptions that they had no previous diagnosis of CA and hence had not received cancer treatment and had no previous experience in TC Qigong.
Ethics approval was obtained from the Human Subjects Ethics Review Subcommittee of the administering institute. The study was explained to each participant and written informed consent was obtained from those who agreed to participate.
All of the assessment procedures were conducted in accordance with the Declaration of Helsinki and took place in the Sports Training and Rehabilitation Laboratory at the administering university. Standardized physical measurements were conducted by a registered physiotherapist who was blinded to the subject group. The demographic and QOL data were collected by a research assistant.
A universal goniometer was used to measure the active ROM of shoulder flexion and abduction for the affected or the dominant arm (for bilateral mastectomy cases and healthy control participants). The ROM of the contralateral (unaffected) shoulder was not assessed because radiotherapy or chemotherapy can also affect the contralateral shoulder, making bilateral comparison unreliable [
The measurements were recorded while the participant was seated and the humerus was rotated externally through complete shoulder flexion and abduction. A standardized protocol was followed to minimize compensatory trunk movements or other trick movements [
All of the participants were first screened for contraindications of isokinetic testing according to the method described by Chan et al. [
During the test, each participant laid on the testing couch in a crook-lying position. The participant’s trunk was stabilized with straps and the nontested hand held onto the handle of the couch. The affected shoulder was positioned at 90° of abduction, elbow in 90° of flexion, and forearm in vertical, with the hand grasping the handle of the wrist/shoulder adapter (i.e., neutral starting position). The longitudinal axis of the humerus was aligned with the rotation axis of the dynamometer. The testing range for the external rotator muscles was from 70° internal rotation to 90° external rotation while the testing range for the internal rotator muscles was from 90° external rotation to 70° internal rotation [
QOL was assessed using the Functional Assessment of Cancer Therapy-Breast (FACT-B, version 4) scale. The reliability and validity of this instrument have been reported to be high [
The FACT-B includes 36 questions divided into five subscales: physical wellbeing (7 items), social/familial wellbeing (7 items), emotional well-being (6 items), functional well-being (7 items), and breast CA-specific concerns (9 items). These subscales comprise QOL-related statements that respondents rate on a 5-point Likert scale of agreement ranging from “not at all” (score 0) to “very much” (score 4). Item scores within a subscale were summed to produce a subscale score. The five subscale scores were then summed to obtain the total FACT-B score (i.e., item scores for all 36 items). A higher score indicates a more favorable QOL [
The Shapiro-Wilk statistic was first used to check the normality of the data. One way analysis of variance (ANOVA) was then used to compare the differences among the TC Qigong, CA-control, and healthy-control groups for the demographic and shoulder active ROM data and the isokinetic peak torques of the shoulder rotator muscles. Bonferroni tests were used to analyze the data post hoc as necessary.
To compare the QOL variables between the TC Qigong CA and CA-control groups, a single multivariate analysis of variance (MANOVA) incorporating all of the FACT-B subscale scores was performed. The results from this analysis showed the effects of the group on all of the FACT-B subscale outcomes and the corresponding Bonferroni-adjusted
If there were any significant between-group differences in the outcome measures, Pearson’s product-moment correlation coefficient (Pearson’s
The characteristics of the participants are presented in Table
Characteristics of participants (mean ± SD).
TC Qigong CA group ( |
CA-control group ( |
Healthy-control group ( |
| |
---|---|---|---|---|
Age (year) |
|
|
|
0.304 |
Height (cm) |
|
|
|
0.859 |
Weight (kg) |
|
|
|
0.063 |
Body mass index (kg/m2) |
|
|
|
0.054 |
Breast CA affected/surgical side ( |
Left = 6; |
Left = 10; |
N/A | — |
Mastectomy ( |
11 | 12 | 0 | — |
Postmastectomy duration (year) |
|
|
N/A | 0.843 |
Radiotherapy ( |
11 | 12 | 0 | — |
Chemotherapy ( |
2 | 1 | 0 | — |
Qigong experience (year) |
|
0 | 0 | — |
Comparison of outcome measures between groups (mean ± SD).
TC Qigong CA group ( |
CA-control group ( |
Healthy-control group ( |
Effect size |
| |
---|---|---|---|---|---|
Shoulder active ROM (affected side/dominant side) | |||||
| |||||
Flexion (degree) |
|
|
|
0.028 | 0.598 |
Abduction (degree) |
|
|
|
0.002 | 0.964 |
Hand behind back (cm) |
|
|
|
0.042 | 0.464 |
| |||||
Body-weight-adjusted isokinetic peak torque at 180°/s (affected side/dominant side) | |||||
| |||||
Shoulder internal rotators (Nm) |
|
|
|
0.198 |
|
Shoulder external rotators (Nm) |
|
|
|
0.210 |
|
| |||||
FACT-B | |||||
| |||||
Physical wellbeing |
|
|
N/A | 0.033 | 0.406 |
Social/family wellbeing |
|
|
N/A | 0.153 | 0.065 |
Emotional wellbeing |
|
|
N/A | 0.089 | 0.167 |
Functional wellbeing |
|
|
N/A | 0.264 | 0.012* |
Breast CA-specific concerns |
|
|
N/A | 0.193 | 0.036* |
Total score |
|
|
N/A | 0.587 | 0.179 |
Analysis of the FACT-B scores revealed no significant differences in the physical, social/familial, or emotional well-being subscale scores, or between the total FACT-B scores of the two CA groups (
Our results demonstrate that all of our participants had a full range of shoulder motion in the flexion and abduction directions compared with the normative data [
In agreement with Harrington et al., who reported reduced isometric shoulder strength, including internal and external rotator muscle strength, in breast CA survivors compared to healthy control participants [
Although TC Qigong training focuses on relaxation and involves minimal muscle work, our results revealed that TC Qigong-trained participants had greater shoulder rotator muscle strength than the CA-control participants who had never received TC Qigong training. The body-weight-adjusted isokinetic peak torques of shoulder internal and external rotators in the TC Qigong-trained participants were actually comparable to those of the healthy control participants (Table
Another encouraging finding was that the scores on the FACT-B functional well-being subscale in the TC Qigong CA group were significantly higher than those of the CA-control group (Table
Despite the potential positive effect of TC Qigong training on functional well-being in breast CA survivors, the exercise may not relieve survivors’ concerns about breast CA-related problems. Our results reveal that the breast CA survivors who participated in TC Qigong training experienced more side effects of conventional cancer treatments (e.g., swollen arm), and their psychological status (e.g., self-esteem relating to sexual attractiveness), as reflected by the FACT-B breast CA-specific concerns score (Table
Regarding the physical, social/family, and emotional well-being subscale scores, no between-group differences were observed in this study (Table
As no between-group differences were found for most of the FACT-B subscale scores, the total FACT-B score, which is the sum of all subscale scores, was similar between the two groups (Table
TC Qigong training appears to improve shoulder rotator muscle strength and functional well-being in breast CA survivors. However, due to the cross-sectional research design and relatively small sample size, we cannot confirm the results without larger-scale, randomized controlled clinical trials. Moreover, some of our participants could not recall the exact type of surgery (e.g., radical or modified mastectomy) they had received and we were unable to retrieve their medical records. Exercise history was also not documented in this study. All these factors may confound the results. Further study may include a more homogenous sample and request the participants to present their surgical or medical records and exercise history during the screening process.
Although there was no obvious impairment of shoulder mobility, impairment of shoulder rotator muscle strength was apparent among the breast CA survivors. Tai Chi Qigong training might improve shoulder muscular strength and, therefore, the functional well-being of breast CA survivors. TC Qigong can be considered as a potential therapeutic intervention for long-term breast CA survivors.
The authors declare that they have no conflict of interests with respect to the authorship or publication of this paper.
The authors would like to thank the Hong Kong Wushu and Art Service Centre for enabling the recruitment of participants and for providing free 18 Forms Tai Chi Internal Qigong training sessions. They are grateful for Dr. KK Mak’s advice on the QOL outcome measures and to Mr. Ken Lee for his advice on oncology rehabilitation.