| Objective:Nordic walking is a type of emerging aerobic exercise, which utilises alpenstock to push the body stepping forward. Recent studies have found that Nordic walking can facilitate the treatment of some diseases. However, the effects of Nordic walking on he treatment of non-alcoholic fatty liver disease (NAFLD) has not been fully nderstood yet. Thus, in this thesis, a 6-month Nordic walking program was as an ntervention to study its effects on the body composition and muscle strength of )ostmenopausal women, who had prediabetic NAFLD. Moreover, the relationships )etween body composition and muscle strength was investigated, so as to provide the eference for the researches on prediabetic NAFLD people. Also, this thesis was med to enhance the life quality and exercise habits of prediabetic NAFLD people by Nordic walking training.Methods:Firstly,27 prediabetic NAFLD postmenopausal women were selected and randomly divided into 2 groups (14 in Exercise Group and 13 in Control Group) by questionnaire, NAFLD diagnosis and blood index measurement. Meanwhile,13 prediabetic postmenopausal women without NAFLD were defined as Reference roup. A 6-month progressive aerobic exercise (Nordic walking) was carried out on he subjects in Exercise Group under supervision, meawhile, the heart rate and rated )erceived exertion (RPE) were measured. In the first month of intervention, the ubjects praciced to get fimiliar with Nordic walking at least twice per week. In the llowing two months, the exercise intensity was upregulated to an intermediate level ith the Nordic walking 2-3 times per week to guarantee the heart rates within the ange of 60%-75% of maximum ones. After three months, an evaluation of ;ardio-pulmonary function and aerobic endurance was carried out on subjects so as to nodify the intensity of the exercise in the following months. Finally, an exercise plan vas determined for the Month 4-6, in which Nordic walking was suggested with 3-4 imes per week. Each time contained 1 hour exercise, including 5-minute warm-up ind 5-minute cool-down exercises. While Control Group were required to keep their ifestyle.The measurements of fatty infiltration of liver (FIL), blood index, muscle itrength and body composition were carried out in Month 0,3 and 6, meanwhile, the lose and physical activities were recorded by questionnaire.Variance analysis was carried out on the results of repeated measurements in ;ach group and chronological order. Meanwhile, an independent t-test was employed to compare the indexes of NAFLD people (Exercise Group and Control Group) and lon-NAFLD people (Reference Group). Furthermore, Pearson correlation analysis ind partial analysis (adjusted for age) were used to show the relationship between body composition and muscle strength. Finally, the incidence between different groups was calculated by Chi-square test. In this thesis, all of the analysis was implemented using SPSS 22.0 (SPSS Inc., Chicago, USA), and p< 0.05 was defined o have statistical significance.Results:After 6-month Nordic walking program, FIL decreased from 14.5±16.6% to .8±5.5% in Exercise Group, insulin level increased slightly and serum lipid profiles as total cholesterol (TC), low-density lipoprotein (LDL-C) improved, while in Control roup no improvement was observed. Also, physical activity (PA) was significantly ncreased in Exercise Group (1865.8METmin/Wk,p=0.037).Weight and Body mass index (BMI) were decreased slightly in Exercise Group nd Control Group. In terms of body composition, no significant differences existed vithin and between groups. However, average lean mass of arms and legs dropped in ontrol Group, while maintained in Exercise Group, in which legs’lean mass even ncreased.In terms of muscle strength, handgrip strength/weight of Exercise Group mproved after 3 months (p=0.013) and 6 months (p=0.001) compared with baseline sults, but Control Group has no improvement. Elbow flexion strength/weight in )oth groups enhanced without significance, and the increment of the first 3 months vas greater in Exercise Group, of the last 3 months kept plateau compared with ontrol Group. Knee extension strength kept increasing in Exercise Group, and xceeded Control Group dramatically after 6 months (p=0.033).As partial correlation (adjusted for age) between body composition and muscle trength showed, in Reference Group knee extension strength was positively orrelated with all regional lean mass (r’=0.62-0.81), so as elbow flexion strength (r’=0.68-0.85), and handgrip strength was positively correlated with the lean mass of rms, legs and Gynoid (r’=0.62-0.73). The strength variables were negatively orrelated with regional fat tissue percentages. In NAFLD people, baseline strength esults also had positive correlations with many muscle mass indexes (r’=0.39-0.58).From the perspective of correlations between variable changes of body composition and muscle strength, some correlations existed only in Control Group, ot Exercise Group, like elbow flexion strength was negatively correlated with body at percentage, regional fat percentage (legs, trunk, Android). After adjusting by eight, handgrip and knee extension strength had negative correlations with relative )ody composition variables, and knee extension strength was correlated with sMM/weight. Slight different relationships occurred after the adjustment of age. While in Exercise Group, A/G was correlated with handgrip and elbow flexion trength, but with opposite trends; after adjusting for weight, elbow flexion strength vas negatively correlated with arms’fat tissue percentage.Conclusion:(1) Six months of Nordic walking program had positive effects on serum lipid profiles and FIL(2) The program maintained their appendicular skeletal muscle mass in Exercise Group.(3) The program improved handgrip strength and knee extension strength significantly in Exercise Group.Therefore, Nordic walking is recommended in middle-aged postmenopausal NAFLD women to enhance their muscle quality and life quality. |
