Endocrinology and Metabolic Syndrome

Biography

Biography: Hidekatsu Yanai

Abstract

Non-exercise activity thermogenesis (NEAT) is the energy expenditure due to physical activities (PA) besides sports-like exercise and resistance training. It includes various activities in daily life such as going to work, attending school, singing, dancing, washing clothes and cleaning floors. We developed the original questionnaire to evaluate NEAT in Japanese people, based on 2011 Compendium of Physical Activities produced by American College of Sports Medicine, by considering Japanese life-style and culture. The questionnaire consisted of 11 question items about locomotive activities and 25 question items about non-locomotive activities. We evaluated each questionnaire item with a score of 1 to 3 points in order of levels of daily PA and then added up the scores to determine the NEAT score.
In our previous study using 45 subjects (22 women and 23 men) with type 2 diabetes who did not take any hypoglycemic, anti-hypertensive, or cholesterol-lowering agents, the NEAT score was negatively correlated with serum insulin levels (r = -0.42, P < 0.05). The NEAT score was also negatively correlated with waist circumference (r = -0.509, P < 0.05) and positively correlated with HDL-C levels (r = 0.494, P < 0.05) in women, and was negatively associated with serum insulin levels (r = -0.732, P < 0.005), systolic (r = -0.482, P < 0.05) and diastolic blood pressure (r = -0.538, P < 0.05) in patients with abdominal obesity. Our study demonstrated that NEAT is associated with amelioration in insulin sensitivity, waist circumference, HDL-C, blood pressure, in patients with type 2 diabetes.
We examined the validity of our NEAT questionnaire by comparing with objectively measured daily PA by using the triaxial accelerometer. The NEAT score was significantly and positively correlated with PA level (PAL) measured by the triaxial accelerometer (r = 0.604, P < 0.001). PAL was also significantly and positively correlated with both the locomotive NEAT score and the non-locomotive NEAT score (r = 0.444, P = 0.001 and r = 0.526, P < 0.001, respectively). The NEAT score measured by the self-reported questionnaire was highly correlated with PAL measured by the triaxial accelerometer.
In type 2 diabetic women, the NEAT score was significantly and negatively correlated with urinary albumin creatinine ratio (UACR) (r = -0.513, P < 0.05) and positively correlated with coefficient of variation of R-R intervals (CVRR) (r = 0.471, P < 0.05). Our study suggested that NEAT is beneficially associated with markers for diabetic nephropathy and neuropathy in type 2 diabetic women.
In patients with type 2 diabetes, multiple regression analysis, adjusted for age, gender, height and weight, revealed that hand grip strength was positively associated with total NEAT scores and  locomotive NEAT scores.
I summarized beneficial effects of NEAT on metabolic parameters in Table 1. An increase of NEAT enhances muscle strength, reduces visceral adiposity and blood pressure, and improves insulin resistance and serum lipids, and is associated with lower risk of diabetic complications.