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Original article
A preliminary study of the effects of Tai Chi and Qigong medical exercise on indicators of metabolic syndrome, glycaemic control, health-related quality of life, and psychological health in adults with elevated blood glucose
  1. X Liu,
  2. Y D Miller,
  3. N W Burton,
  4. W J Brown
  1. University of Queensland, St Lucia Queensland, Australia
  1. Correspondence to Wendy J Brown, School of Human Movement Studies, University of Queensland, Level 5, Building 26, St Lucia Queensland, 4072 Australia; wbrown{at}hms.uq.edu.au

Abstract

Objectives To evaluate the feasibility, acceptability and effects of a Tai Chi and Qigong exercise programme in adults with elevated blood glucose.

Design, Setting, and Participants A single group pre–post feasibility trial with 11 participants (3 male and 8 female; aged 42–65 years) with elevated blood glucose.

Intervention Participants attended Tai Chi and Qigong exercise training for 1 to 1.5 h, 3 times per week for 12 weeks, and were encouraged to practise the exercises at home.

Main Outcome Measures Indicators of metabolic syndrome (body mass index (BMI), waist circumference, blood pressure, fasting blood glucose, triglycerides, HDL-cholesterol); glucose control (HbA1c, fasting insulin and insulin resistance (HOMA)); health-related quality of life; stress and depressive symptoms.

Results There was good adherence and high acceptability. There were significant improvements in four of the seven indicators of metabolic syndrome including BMI (mean difference −1.05, p<0.001), waist circumference (−2.80 cm, p<0.05), and systolic (−11.64 mm Hg, p<0.01) and diastolic blood pressure (−9.73 mm Hg, p<0.001), as well as in HbA1c (−0.32%, p<0.01), insulin resistance (−0.53, p<0.05), stress (−2.27, p<0.05), depressive symptoms (−3.60, p<0.05), and the SF-36 mental health summary score (5.13, p<0.05) and subscales for general health (19.00, p<0.01), mental health (10.55, p<0.01) and vitality (23.18, p<0.05).

Conclusions The programme was feasible and acceptable and participants showed improvements in metabolic and psychological variables. A larger controlled trial is now needed to confirm these promising preliminary results.

https://doi.org/10.1136/bjsm.2008.051144

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    The prevalence of diabetes is increasing throughout the world. In 2000, 170 million people worldwide had diabetes, a number which is expected to rise to over 360 million by 2030.1 The constellation of risk factors known as metabolic syndrome2 (see table 1) has been shown to be highly predictive of the development of diabetes and other health problems.3 4 Given the dramatically increasing prevalence of diabetes, and the associated premature mortality, disability, complications, and social and economic costs, management of metabolic syndrome is of paramount importance to public health.

    View this table:
    Table 1

    Definition of metabolic syndrome

    Previous studies have shown that physical activity plays an integral role in preventing progression to type 2 diabetes, as well as in managing type 2 diabetes.5,–,7 Many individuals, however, are unable or unwilling to participate in conventional types of physical activity, such as strength training and gym-based exercises, which have been shown to be beneficial in the control of diabetes.8

    Tai Chi and Qigong are the two most popular Chinese medical exercises worldwide. Tai Chi has been shown to have similar energy expenditure to other moderate-intensity activities, such as walking at a speed of 6 km/h,9 and to have both physiological and psychological benefits.10 These Chinese exercises may be easier to learn than gym-based exercises, and do not require any complicated or expensive equipment. Thus, Tai Chi and Qigong may provide an alternative form of physical activity for middle-aged and older people with elevated blood glucose who may be fearful of injury and additional perceived negative consequences of other forms of exercise.8 There is now growing evidence to suggest that Tai Chi and Qigong may improve indices of glycaemic control in people with diabetes,11 but to date no studies have focused specifically on the effects of Chinese medical exercises on metabolic syndrome.

    Tai Chi/Qigong has previously been shown to improve indicators of health-related quality of life and psychological health.10 12 These benefits may be particularly important for people at risk of or with diabetes, who may be more vulnerable to compromised health-related quality of life and poor psychological health13 14 and subsequently poor self-management practices, increased healthcare costs, and adverse outcomes.13 15 Studies have not, however, examined the psychological effects of Tai Chi/Qigong in people with or at risk of developing diabetes.

    This study examined the feasibility and acceptability of a Tai Chi/Qigong programme and its effects on indicators of metabolic syndrome, glycaemic control, health-related quality of life and psychological health, in adults with elevated blood glucose levels.

    Methods

    Participants and study design

    The study was awarded ethical clearance by the Medical Research Ethics Committee at the University of Queensland (Australia). It was a single-group pre–post trial with outcome measures assessed immediately prior to and after a 12 week Tai Chi and Qigong programme. Participants were recruited using a range of methods including letters of invitation to members of Diabetes Australia Queensland, referral from general practitioners (GP) and public advertisements in the local print media. The eligibility and exclusion criteria are shown in table 2. From 32 initial respondents, 11 obtained clearance to participate in the programme from their General Practitioner, and attended baseline assessment. Most were already meeting national physical activity guidelines.16 Given the low number of eligible volunteers, the exclusion criterion of being physically active was relaxed, and all 11 agreed to participate in the study.

    View this table:
    Table 2

    Eligibility and exclusion criteria for participation in the study

    The intervention

    In addition to their usual care, participants attended three Tai Chi/Qigong training classes per week for 12 weeks, under the guidance of a Tai Chi/Qigong instructor. Participants also received a video/DVD demonstrating the exercises, and were encouraged to practise the movements at home on days when they did not attend the group sessions. The exercise was KaiMai Tai Chi/Qigong style.17 Each session lasted 1 to 1.5 h with 28 minutes’ warm-up, 30 minutes’ practice, and 6 to 28 minutes’ cool-down. The intensity of the exercise during each session varied among participants according to individual health and fitness levels. The duration of the classes was progressively increased from 1 h to 1.5 h throughout the 12 weeks of the programme.

    Measures

    Having given informed consent, all participants completed the baseline assessment up to 1 week prior to the start of the intervention. Each assessment was conducted at the University by a research assistant, and required participants to provide a fasting venous blood sample, complete a questionnaire, and undergo physical measurements. Baseline assessment procedures were replicated at the end of the 12 week intervention period.

    Haematological measurements

    A fasting blood sample was collected from the antecubital vein at least 48 h postexercise for analysis of HbA1c, triglycerides, HDL-cholesterol, plasma glucose and serum insulin. HbA1c was measured immediately using a DCA 2000+ Analyzer (Bayer Corporation, Elkhart, Indiana, USA). Baseline and postintervention plasma and serum samples were stored at −80°C until assayed, at the same time, on completion of the intervention. Blood glucose, triglycerides and HDL-cholesterol were measured on a Cobas Autoanalyser using a Thermotrace Kit (Thermo Electron, Noble Park, Victoria, Australia). Serum insulin was determined using an enzyme-linked immunosorbent assay (ELISA) kit (DRG Diagnostics, Marburg, Germany). Insulin resistance was calculated using the homeostasis model assessment (HOMA) index formula: Insulin resistance = fasting blood glucose (mmol/l)×fasting insulin (μU/ml)/22.5.18

    Questionnaire

    The questionnaire included items to assess age, gender, country of birth, family history of diabetes, language spoken at home, physical activity, health-related quality of life, stress and depressive symptoms. At postintervention, open-ended questions were added to assess the acceptability and feasibility of the Tai Chi/Qigong programme. Items asked about perceived benefits of and barriers to participating in the programme, comments on the DVD/video provided for at-home practice, and intentions regarding physical activity after the intervention.

    Physical measures

    Waist circumference, height and weight were measured using standard protocols.19 Body mass index (BMI) was calculated as weight (kg) divided by height squared (m2). Resting blood pressure was measured using a portable mercury sphygmomanometer (ALPK2, Japan) following standard protocols.20

    Physical activity (PA)

    PA was assessed using a 1 week recall questionnaire adapted from the Active Australia Survey.21 The items have demonstrated acceptable test–retest reliability.22

    Health-related quality of life (QOL)

    QOL was assessed using the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36).23 The mental and physical health components’ summary scores and eight subscale scores (general health, physical functioning, role–physical, role–emotional, social functioning, bodily pain, mental health, and vitality) were calculated.24 25 Scores ranged from 0 to 100, with higher scores representing better QOL. The SF-36 has been shown to be reliable and valid for Australian adults.23

    Psychological measures

    Stress was assessed using the Perceived Stress Questionnaire (PSQ).26 The scale included 11 items, and asked participants to rate how stressed they had been in the last 3 months in 10 specific domains (eg, “own health”, “work/employment”). Each item was rated on a five-point scale, with response levels from not at all stressed to extremely stressed. Scores ranged from 0 to 4. The PSQ scale has good internal reliability, unifactoriality, and content validity.26

    Depressive symptoms were assessed using the short form of the CES-D Depression Scale. Participants indicated on a four-point scale the frequency of experiencing each of 10 symptoms during the past week, and a cutoff score of >10 was defined as clinical depression.27 The short form CES-D 10 shows good predictive accuracy when compared with the CES-D 20 (k = 0.97, p<0.001).28

    Adherence, acceptability, and feasibility

    Records of attendance at the group sessions, and reasons for non-attendance, were recorded by the exercise instructor at each class. Participants were asked to keep a diary to monitor their at-home practice during the intervention.

    Statistical analyses

    Statistical analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 15.0 software. Means and standard deviations (SD) were calculated for normally distributed continuous variables. Differences between baseline and postintervention measures were analysed using paired t tests; confidence intervals (95% CI) were calculated to describe mean differences. As physical activity was not normally distributed, medians and interquartile ranges were calculated to compare baseline and postintervention values. McNemar's χ2 test was conducted to examine within-participant change in indicators of metabolic syndrome and change in clinical depression from baseline to postintervention. Unless otherwise noted, significance was set at an alpha level of 0.05.

    Results

    Participant characteristics

    Eleven participants (three men, eight women, age 42–65 years) participated in this pilot study. Only four were born in Australia but all except one spoke English at home. Five had fasting blood glucose levels indicative of elevated blood glucose (5.8–6.4 mmol/l) and six had levels ≥7 mmol/l (7–8.7 mmol/l). BMI levels ranged from 18.5 to 36.4 kg/m2. Seven participants met the criteria for diagnosis of metabolic syndrome according to the International Diabetes Federation definition of metabolic syndrome (shown in table 1).2 Eight participants reported a family history of diabetes, and nine met the current Australian public health guidelines for physical activity (i.e. ≥150 minutes of moderate physical activity per week) at baseline.16

    Adherence, acceptability and feasibility

    Adherence to the programme was very good, with 11 participants retained during the 12 week programme. On average participants attended 92% of the group classes with absence attributed to competing family or work commitments. Compliance with the “at-home” sessions was also very good with participants completing 78% of the recommended “at-home” training sessions.

    Participants reported both physical and psychological benefits from the programme. Perceived physical benefits included improvements in energy levels, physical wellbeing, sleeping patterns, bladder function, flexibility and endurance, blood circulation in the legs, breathing, muscle tone, immunity, pain reduction; a reduced need for other therapies; and fewer food cravings. Reported psychological benefits included improved mood, confidence, self-esteem and coping; less stress; improved training motivation; and positive changes in life perspective and family harmony.

    Due to a lack of energy and physical strength prior to participating in the programme, some participants experienced initial transient musculoskeletal soreness, but this subsided as the programme continued. Some participants reported pre-existing physical problems which required some of the exercises to be modified. Improvements in some of these problems were reported during the exercise programme.

    All participants reported that the DVD/video was useful for their learning and training, with comments indicating that it enhanced motivation and assisted with memorising the movements. All participants indicated that they would like to continue with this Tai Chi/Qigong programme at least weekly.

    Changes in indicators of metabolic syndrome and glycaemic control

    Mean changes in indicators of metabolic syndrome and glycaemic control from baseline to postintervention are shown in table 3. There were significant improvements in body weight (mean difference −2.96 kg (95% CI −4.13 to −1.79), p<0.001), in four of the seven indicators of metabolic syndrome (BMI, waist circumference, systolic and diastolic blood pressure) and in the three additional indicators of glycaemic control (HbA1c, insulin and insulin resistance). There were no significant changes in the three remaining indicators of metabolic syndrome (fasting blood glucose, triglycerides and HDL-cholesterol), but downward trends in these three haematological measures were observed. Although this was not statistically significant, the percentage of participants with metabolic syndrome decreased from 64% to 36%.

    View this table:
    Table 3

    Changes in weight and indicators of metabolic syndrome and glycaemic control (n = 11)

    Changes in health-related quality of life

    Mean changes in SF-36 scores from baseline to postintervention are shown in table 4. Significant improvements were found in general health (p<0.01), mental health (p<0.01) and vitality (p<0.05), and the mental components summary score (p<0.05). There was also a trend towards a significant improvement in the physical component summary score (p = 0.092).

    View this table:
    Table 4

    Changes in indicators of health-related quality of life and psychological health (n = 11)

    Changes in indicators of psychological health

    Mean changes in PSQ and CESD-10 scores from baseline to postintervention are shown in table 4. Significant improvements were found for measures of stress (p<0.05) and depressive symptoms (p<0.05). Although this was not statistically significant, the proportion of participants with clinical levels of depressive symptoms decreased from 60% to 20%.

    Discussion

    This 12 week Tai Chi/Qigong intervention resulted in significant improvements in four indicators of metabolic syndrome (BMI, waist circumference, systolic and diastolic blood pressure), as well as in health-related quality of life (SF-36 general health, mental health, vitality and the mental components summary score) and psychological health (stress and depressive symptoms) in a small group of 11 participants.

    Although most of the participants reported some difficulties with the exercises at the beginning of the programme, this did not influence class attendance or adherence to at-home practice recommendations. These physical difficulties subsided with progression of the programme; a pattern that is commonly recognised in physical activity training. Participants indicated that they were able to follow the instructor's directions, and the exercises were considered acceptable. Although some participants reported difficulty making time to attend the class three times each week (mainly due to family or work commitments), the high attendance at group sessions suggests that the majority were able to overcome these barriers. Moreover, none of the participants dropped out of the programme, and all were available for final assessment after 12 weeks.

    Although the majority of participants in this study were meeting the Australian physical activity guidelines before commencing the programme, this did not control their risk factors for metabolic syndrome. As there was no evidence of any change in duration of physical activity from pre- to post programme, the improvement in risk factors observed here is likely to be attributable to participation in this specific Tai Chi/Qigong programme, which likely replaced the participants’ preprogramme activities.

    The changes in body weight and waist circumference were consistent with results reported by Dunstan et al following a 3 month high-intensity progressive resistance training programme plus dietary intervention, in people with diabetes.6 In contrast, Castaneda et al7 reported that body weight remained stable in both their high-intensity progressive resistance training group and a control group at 4 months, and Mourier et al29 reported no significant change in waist circumference after a 10 week aerobic training programme for people with diabetes. Previous Tai Chi/Qigong studies have not reported significant changes in body weight or BMI.30 31

    The significant reductions in adiposity variables in the current study are noteworthy because central obesity is integral to the definition and development of metabolic syndrome and diabetes.2 32 While the mechanisms responsible for these changes in BMI and waist circumference cannot be directly determined from the data collected in this study, it is possible that the moderate-intensity Tai Chi/Qigong exercise may have been at an optimal intensity for fat metabolism.33

    The significant reductions in both systolic and diastolic blood pressure in this study confirm the findings of a previous Tai Chi intervention study,34 and a review of 30 Qigong studies,35 which concluded that practising Qigong may have a positive effect on hypertension. In contrast to the reduction observed here, Dunstan et al6 did not find any changes in systolic or diastolic blood pressure after 3 months of resistance training in people with diabetes.

    Although there were no statistically significant changes in fasting blood glucose or insulin, the average reduction in fasting insulin of almost 10 pmol/l produced a significant improvement in insulin resistance after this 12 week programme. In contrast, both Dunstan et al6 and Castaneda et al7 reported that fasting blood glucose and insulin levels remained unchanged during their resistance training interventions, so that insulin resistance did not change. The mean change in insulin resistance reported here (0.53) was similar to that reported in the SLIM study5 (0.72), after 1 year of a combined exercise and diet intervention. According to the World Health Organization, insulin resistance is integral to the definition and development of metabolic syndrome.36 It is also recognised as a strong predictor of diabetes, cardiovascular disease and stroke.4 The reduction of 0.53 units in insulin resistance in this study may therefore be clinically meaningful, and partly attributable to improvements in central obesity and adipocyte insulin resistance.32

    The small but statistically significant reduction in HbA1c (0.3% (p<0.01)) after 12 weeks was greater than that reported by Tessier et al37 (0.2%) following a 16 week walking, cycling and weight training intervention study. The clinical significance of this finding is, however, unclear. Dunstan et al6 have suggested that an improvement in HbA1c of 0.6% (which was observed after 3 months of resistance training) does have clinical significance. However, that study involved a combination of high-intensity resistance training and a healthy eating plan, so the unique effect of the exercise programme could not be ascertained. The low initial mean HbA1c level (5.6%) of the study sample and the relatively short-term intervention of the current study may partially explain the small change in HbA1c.

    Importantly, three of the seven (43%) participants who had metabolic syndrome at preintervention no longer met the diagnostic criteria for metabolic syndrome at postintervention. Clearly the small sample size does not allow us to show any statistical significance here, but the findings add support to the notion that this kind of exercise may have a role to play in controlling or even perhaps reversing metabolic syndrome in some people.

    At baseline, mean scores on the SF-36 subscales were lower than national norms,25 reflecting the overall poorer health-related quality of life of this study sample. This is consistent with other research.14 After the 12 week programme, there were significant improvements in general health, mental health and vitality, and in the SF-36 mental components summary score. These findings are consistent with those from a 10 week Tai Chi programme12 for participants without diabetes, and those of a review indicating psychological benefits from Tai Chi in patients with chronic conditions.10 Wiesinger et al's study with a sample of people with diabetes reported that aerobic physical training significantly improved vitality scores, although this was over a 4 month period and at a more vigorous intensity than in the current study.38 The current findings also support previous research reporting that regular exercise can reduce depressive symptoms.39 Although this was not statistically significant, the proportion of participants categorised as having clinical depression decreased from 60% to 20% from pre- to postintervention. Improvements in general health and vitality may be especially important for people with diabetes or raised blood glucose levels, many of whom report suffering from tiredness and lack of energy. Improvements in psychological wellbeing among those with prediabetes or diabetes may decrease the risk of poor self-management practices, increased healthcare costs, and adverse outcomes.13 15

    What is already known on this topic

    • ▶. Physical activity plays an integral role in the prevention and management of type 2 diabetes. Many individuals, however, are unable or unwilling to participate in conventional types of physical activity, such as strength training and gym-based exercises.

    • ▶. Preliminary evidence suggests that traditional Chinese medical exercises (Tai Chi and Qigong) may be helpful in the management of diabetes, and in improving indicators of health-related quality of life and psychological health.

    What this study adds

    • ▶. This pilot study provides evidence on the feasibility, acceptability and effects of a Tai Chi and Qigong medical exercise programme for improving indicators of metabolic syndrome, glycaemic control, health-related quality of life and psychological health. The study provides valuable data on which sample size calculations for future controlled studies can be based.

    • ▶. The major strengths were the innovative intervention (based on a unique programme of Kai Mai style Tai Chi and Qigong developed specifically for diabetes control) and the inclusion of a range of outcome indicators. Given the lack of a control group and small sample size, the results must be viewed as cautiously optimistic.

    Conclusion

    This feasibility study of a 12 week Tai Chi/Qigong intervention found that the programme was acceptable to participants and resulted in significant improvements in indicators of metabolic syndrome, glycaemic control, health-related quality of life and psychological health in adults with elevated blood glucose. These findings provide grounds for cautious optimism about a role for this Tai Chi and Qigong programme in the management of patients who are at risk of developing type 2 diabetes.

    Acknowledgments

    We would like to thank Diabetes Australia Queensland for their assistance with recruitment, and the technical staff who assisted with screening and measurement (Natalie Stroble and Cecilia Shing). The Tai Chi and Qigong programme was developed by Dr Xin Liu. We would also like to thank the participants for their commitment to this study.

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    Footnotes

    • Funding This research project was funded by a grant from the Diabetes Australia Research Trust. Dr Liu was the recipient of a University of Queensland scholarship. Dr Miller and Dr Burton were supported by NHMRC capacity building (Owen, Brown, Bauman and Trost; #252977) and programe (Owen, Bauman and Brown; #301200) grants in physical activity and health at the School of Human Movement Studies, University of Queensland.

    • Competing interests None.