Adiponectin Increase in Mildly Obese Women After Massage Treatment

Obesity and unfavorable body fat distribution decrease overall health, leading to health problems such as type 2 diabetes, coronary artery disease, and hypertension, ^{1 –3} all of which drastically reduce healthy life expectancy. ⁴ In Japan's super-aging society, the esthetic and health industries are quickly developing, with several esthetic salons advertising “massage for weight loss.” In the United States, too, massage is a frequently used form of complementary and alternative medicine for weight control. ⁵

Recent research on obesity indicates that reduced plasma concentration of adiponectin, an adipocyte-derived hormone, leads to increases in obesity-linked diseases such as metabolic syndrome, diabetes, cardiovascular diseases, and cancer. ⁴ Obesity results in large adipocytes, causing lower secretion of adiponectin. ⁶ Mouse models have shown that higher expression of adiponectin results in better health and longevity. ⁷

Scientific clinical studies examining manual massage's effects on obesity and related outcomes are not apparent in the literature. The researchers conducted a within-subject pre–post study to gather preliminary data examining the extent to which manual massage influences weight reduction and abdominal circumference (primary outcomes) and adiponectin concentration in blood (secondary outcome) for mildly obese Japanese women. This study was performed at Tsukuba University of Technology in June 2010 and was approved by the university's Medical Ethics Committee.

Nine female postmenopausal participants (mean age ± SD: 56.8 ± 4.0 years; mean body mass index [BMI] ± SD: 27.7 ± 1.4) were recruited through a public relations brochure. The eligibility criterion was BMI of 25–30, which is defined as mild obesity by the Japan Society for the Study of Obesity. ^8,9 After initial assessment (A1), a 2-month duration of no intervention was set as a baseline, and a second assessment (A2) was completed. One week after A2, weekly 40-min massage was performed for 2 months (total of eight sessions). The third assessment (A3) was performed 1 week after the final massage session. The massage protocol and techniques (stroking, kneading, and pressure) were based on a book by Maxwell-Hudson. ¹⁰ Therapists massaged the whole body, including neck, shoulders, back, lower back, chest, abdomen, upper limbs and hands, and lower limbs and feet. The abdominal area was massaged for 10 min, and therapists stimulated to the depth of the adipose tissue. The same observer measured body weight and circumference at the umbilicus as the abdominal circumference, and blood samples (normal level of adiponectin: over 4 μg/mL) were taken at close to 1:00 pm, in A1, A2, and A3, before participants ate lunch. Data were analyzed by the Friedman test, and the Wilcoxon signed-rank test was used as a post hoc test with p values amended by the Bonferroni method, using IBM SPSS Statistics 21.

All the participants completed the study. Body weight (median [interquartile range, IQR]: A1, 68.50 [60.55–71.85] kg; A2, 68.30 [60.75–72.75] kg; A3, 68.40 [61.70–71.90] kg) and abdominal circumference (median [IQR]: A1, 96.50 [90.75–100.75] cm; A2, 93.00 [89.50–100.75] cm; A3, 93.50 [90.00–100.75] cm) did not significantly differ (p = 0.717, p = 0.625, respectively). However, a significant difference was found in adiponectin levels in blood (median [IQR]: A1, 7.70 [4.30–9.85] μg/mL; A2, 7.60 [4.75–10.90] μg/mL; A3, 8.20 [5.30–12.05] μg/mL) (p = 0.002), and post hoc testing revealed significant differences between A1 and A3 (p = 0.011) and between A2 and A3 (p = 0.007), but no difference between A1 and A2 (p = 0.058) (Fig. 1). According to the participants' self-reports, they did not change their daily lifestyle, such as their amount and quality of daily diet and exercise level, during the study duration.

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FIG. 1.

Changes in outcome measures. Median, interquartile range, maximal value, and minimum value in each outcome at each assessment time are shown. A1: Assessment 1 (before control). A2: Assessment 2 (after control, before massage). A3: Assessment 3 (after massage). Body weight: Friedman test p = 0.717. Abdominal circumference: Friedman test p = 0.625. Adiponectin concentration: Friedman test p = 0.002. Post hoc test between A1 and A2 p = 0.058 (not significant), between A2 and A3 p = 0.007 (significant), and between A1 and A3 p = 0.011 (significant). p-Values were calculated using the Wilcoxon signed-rank test, and p-values were amended with the Bonferroni method (significant p-values were <0.0166). Normal adiponectin levels are over 4 μg/mL.

Manual massage may stimulate subcutaneous adipose tissue, which may be associated with increased hormone levels of adiponectin despite obesity. This suggests that massage treatment may play a supplemental role in natural hormone production.

Some limitations of the study should be noted. The findings must be interpreted with caution due to the very small sample size; in addition, the study design was a single-subject AB design, and the data for this study are somewhat old. Subsequent trials with a larger sample size and more robust study design are needed to confirm and further explore these findings.

In conclusion, manual massage did not lead to weight loss or abdominal circumference reduction in the population of the present study, but adiponectin levels significantly increased, providing novel preliminary evidence in need of further investigation.