Effects of muscular and aqua aerobic combined exercise on metabolic indices in elderly women with metabolic syndrome.

The purpose of this study was to investigate the effects of muscle strengthening exercise using elastic thera-band and aquatic aerobic combined exercise on metabolic syndrome index in elderly with metabolic syndrome. Fifty-four were assigned to muscle strengthening exercise group (n = 19), aquatic aerobic exercise group (n = 19), and combined exercise group (n = 16). The muscle strength exercise, aquatic aerobic exercise and combined exercise were provided three times a week for 12 weeks. Metabolic syndrome indices[Fasting blood glucose, triglyceride, high density lipoprotein cholesterol (HDL-C), systolic blood pressure, diastolic blood pressure and waist circumference] were measured before and after the program. One-way ANOVA, paired t-test and two-way repeated ANOVA were used with the SPSS program for data analysis. There was a significant difference in triglyceride (p < .001), HDL-C (p = .010) and waist circumference (p = .016). Triglyceride and waist circumference was significantly decreased in combined group than muscle strength exercise group and aquatic exercise group. HDL-C was significantly increased in combined group than muscle strength exercise group. The results indicate that combined exercise was more effective in the improvement of dyslipidemia and abdominal obesity.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

According to the in-depth survey report on the 2005 Korea national Health and Nutrition Examination Survey, the overall prevalence rate of the metabolic syndrome tends to increase with older ages by comparison of the gender and ages, the male group with the age of 50-59 years old reaches the highest point of 44.7% of the assumed prevalence rate of the metabolic syndrome and the female group with older than 70 years old marks the highest point of 55.1% due to the increase in the prevalence rate of the metabolic syndrome with older ages. In particular, the prevalence rate of the metabolic syndrome for the female with the age of 60-69 and over 70 years old is significantly higher than the male group and it is indicated that it is required to manage the metabolic syndrome for the elderly female group [1]. In particular, the women in the menopause are exposed to the danger of the metabolic diseases due to various harmful side effects of the menopause and the prevalence rate is also high [2]. However, only 39.1% of the senior perform regular exercise (more than 150 minute per week) even though they should perform physical activities to manage such metabolic diseases [3].

The aerobics, one of the various exercises performed in the metabolic syndrome, is good to reduce the abdominal fat but it is reported that the resistance exercise increases the metabolic syndrome by upgrading the muscle quantity and the effect of the aerobics [4]. The effects of the combined exercise are proven by Kim et al. [5] who showed the improvement in the metabolic syndrome indicators, decrease in the blood sugar level and insulin level and increase in the physical fitness by performing the combined exercise of aerobic and resistance exercise for middle-aged women with the metabolic syndrome and Ban et al. [6] who showed effects in the body composition, metabolic syndrome indicator and physical fitness through the combined exercise for obese middle-aged women. In particular, the combined exercise is recommended as people claim burden and boredom in time due to aerobic and muscular strength exercise [7]. However, the aquatic exercise which may reduce the burden on the joints may be a useful alternative by utilizing physical features of the medium including static water pressure and temperature, buoyancy and muscular strength exercise using the elastic resistance for the senior due to injury or damage from excessive physical activities. Considering the elements of the physical fitness in the senior, the fitness using relatively safe elastic band is widely used and the aqua aerobic is used for certain disease groups with burden on the joints but it is confirmed effective in the physical fitness, physical composition and metabolic syndrome indicators [8].

Various exercise methods have been applied based on such positive effects of the exercise but in many cases, one exercise with aerobic or resistance exercise is performed or mainly based on the aerobic exercise on the ground or in the water. First, the studies on comparing the ground and underwater sports include Kim et al. [9] reporting that the aerobic on the ground and in the water is more effective than the ground aerobic in the metabolic syndrome indicators for metabolic syndrome patients and Kim [10] reports that the ground and underwater exercise shows significant difference in the CRP and Fibrinogen and the underwater exercise is more effective than the ground exercise. The positive effects in the ground and underwater exercise are different for the metabolic syndrome. The studies on walking on the ground and underwater improve the cardiovascular prediction indicators for healthy people [11]. There are rare prior studies on the ground and underwater exercise simultaneously but it is reported that the chronic hemiplegic patients with ground and underwater exercise show positive effect on the physical fitness for daily activities and range of motion than only with the underwater exercise [12].

Most prior studies cover the exercise program for 60 minutes with the warm-up, cool-down, aerobic and resistance exercise in a program. The study compares the effect of combined exercise with the ground band exercise (once a week) and aqua aerobic exercise (twice a week) on the metabolic syndrome indicators for female women with the metabolic syndrome to a single exercise and is used as the basic data to form effective health promotion program.

RESEARCH METHOD

Research subjects

The initial research subjects are 25 people in the muscular strength group using the elastic band (hereafter the muscle strengthening exercise using elastic thera-band), 25 people in the aqua aerobic exercise group and 25 people in the combined exercise group with the muscle strengthening exercise using elastic thera-band and the aqua aerobic exercise. However, the subjects without continuous participation or not in the post-test after the exercise program are removed and the final participants are 54 including 19 in the muscle strengthening exercise using elastic thera-band group, 19 in the aqua aerobic exercise group and 16 in the combined exercise group (dropout rate: 11.6%).

The sample number of the study is calculated based on the fact a total of 45 subjects are required to achieve effect size of 0.25, power of test .95 and alpha level of .05. in the ANOVA test of the G*power [13]. General characteristics of the subjects are in Table 1.

Table 1.

General characteristics of the subjects

Characteristics	Muscle	Aqua	Combined
Age (year)	71.20±2.60	70.89±3.32	71.14±3.11
Height (cm)	153.68±5.08	155.33±3.75	154.94±5.72
Weight (kg)	58.27±5.70	63.24±5.62	59.38±6.46
Body mass index (kg/m2)	24.72±2.58	26.19±1.90	24.75±2.63

Muscle; Muscle strengthening exercise using elastic thera-band, Aqua; Aqua aerobic exercise, Combined; Muscle strengthening exercise using elastic thera-band and aqua aerobic exercise

The selection criteria are 3 of 5 diagnosis criteria for the metabolic syndrome below and the subjects are women older than 65 years old, may communication with each other and have not done continuous exercise for 6 months prior to the program initiation. The diagnosis criteria for the metabolic syndrome is based on the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP) III [14] and uses the waist circumference proposed by the Korean Society for the Study of Obesity [15] and the downward standard of the impaired fasting glucose proposed by the American Diabetes Association [16].

Higher than 100mg/dl of the fasting blood sugar, insulin injection or oral hypoglycaemic agent administration

Higher than 150mg/dl of the triglyceride

Higher than 150mg/dl of the triglyceride

Less than 50mg/dl of the high density lipoprotein-Cholesterol; hereafter HDL-C)

Higher than 130mmHg of the systolic blood pressure or 85mmHg of the diastolic blood pressure, currently under hypertension drugs

Longer than 85cm of the waist circumference

Data selection period and method

The data selection period is between March and July 2013 and is performed for each group of participants who agree to join the program prepared by the healthcare center. The metabolic syndrome indicators (fasting blood sugar, blood pressure, triglyceride, HDL-C and waist circumference) are measured prior to performing the muscle strengthening exercise using elastic thera-band, aqua aerobic exercise and combined exercise and measured again after completing the 12-week program.

Intervention

The combined exercise program with the muscle strengthening exercise using elastic thera-band and the aqua aerobic exercise is shown in Table 2.

Table 2.

Exercise program

Order	Contents	Week/Intensity		BPM/Set	Time (min)
Warm-up	Stretching	Band Exercise	Combined Exercise		10
Muscle strength exercise	• Arm curl	1 weeks/ 11-12 RPE	1-2weeks/ 11-12 RPE	15/3,15/2	40
	• Triceps extension
	• Bent over row
	• Good morning
	• Shoulder press	2-6 weeks/ 13-14 RPE	3-7 weeks/ 13-14 RPE	20/2,15/3
	• Up-right row
	• Squat
	• Lunge	7-12 weeks/ 15-16 RPE	8-12 weeks/ 15-16 RPE	20/3,20/2
	• Chest press
	• Crunch
	• Leg raise
Aqua aerobic exercise	• Bounce-front, back, slide, side, twist	1-2 weeks/ 11-12 RPE		110~120	40
	• Knee jogging-narrow, wide
	• Jumping jack-front, back, side
	• Scissors & pendulum
	• Jazz kick & soccer kick
	• Rocking horse	3-7 weeks/ 40 13-14 RPE		120∼140
	• Leaping- front, side
	• Heel cross, ankle reach
	• Kick & hold, mambo step,
	• Leg swing, kick swing
	• Frog jump, tuck jump
	• Touch bounce, jig,	8-12 weeks/ 15-16 RPE		120∼140
	• Leg curl
	• Twist heel & toe
	• Kick-front, back, side
	• Side step, step & cross
	• Ankle inversion, eversion, dorsiflexion, plantar flexion
Cool-down	Stretching				10

RPE: Rating of perceived exertion

Muscle strengthening exercise using elastic thera-band

The muscular strength exercise program goes for 60 minutes a day, 3 times a week with 10 minutes of warm-up, 10 minutes of cool-down and 40 minutes of main exercise using the thera-band with elasticity and the exercise strength uses the Rating of Perceived Exertion (hereafter, RPE). The study refers to the exercise material which provides elderly sports, youth and vigor [17,18] and the material is modified to the study. The first one week is the adaptation period with yellow and red bands with the strength of 11-12 (light), with the strength of 13-14 (somewhat Hard) and red and yellow bands with the strength of 15-16 (hard) to gradually increase the exercise strength. The strength of the elastic band (Thera-band; Hygenic Co., USA) consists of yellow (0.7/1.0/1.1 kg, 20/40/70 cm), red (0.9/1.6/2.0 kg, 20/40/70 cm) and green (1.1/1.9/2.3 kg, 20/40/70 cm) bands and the band is selected to perform an action more than 10 times.

Aqua aerobic exercise

The aqua aerobic exercise consists of a program of 60 minutes including 10 minutes of warm-up, 10 minutes of cool-down and 40 minutes of main exercise 3 times a week based on the manual used by the Korea Aquatic Exercise Association and the exercise strength uses the RPE.

The warm-up is for 10 minutes of standing jump to maintain the body temperature. The main exercise implements the gradual increase from the adaptation period of the first 1-2 weeks with the strength of 11-12 (light), 3-7 weeks with the strength of 13-14 (somewhat hard) and 8-12 weeks with the strength of 15-16 (hard). The cool-down is 10 minutes of the dynamic stretching. Also, the beat, important in the movement of the subject in the aquatic aerobic, is 110-140bpm, 110-120bpm for the cool-down and jogging, dance and flexible gymnastics are applied in the water to strengthen the cardiovascular endurance with 120-140bpm to increase the calorie consumption.

Combined exercise

The combined exercise consists of the muscle strengthening exercise using elastic thera-band once a week and the aqua aerobic exercise twice a week for 60 minutes each with 10 minutes of warm-up, 10 minutes of cool-down and 40 minutes of main exercise.

The aqua aerobic exercise is performed the same with the single exercise program and the resistance exercise uses the yellow and red bands with the strength of 11-12 for the first 1-2 weeks (light), yellow and red bands with the strength of 13-14 for 3-7 weeks (somewhat hard) and the red band with the strength of 15-16 (hard).

Instruments

Exsanguination and blood analysis

The smoking and drinking are prohibited 24 hours before the exsanguination and the exsanguination is performed with fasting for 12 hours. The blood of 5ml is exsanguinated from the antebrachial vein and the test is performed in the clinical pathology room. The items under the test are the fasting blood sugar, triglyceride and HDL-C.

Blood pressure

The blood pressure is measured by the mercury hematomanometer (605p; Yamasu, Japan) after taking a rest for more than 30 minutes after the subject arrives the healthcare center

Waist circumference

The waist circumference is measured after the normal breath in parallel with the belly button using the tape measure. The measurement unit is cm.

Data analysis

The data analysis is performed by the statistics program, SPSS 18.0. General characteristics in the subjects are described with the average and the standard deviation and the ANOVA is performed for the homogeneity verification. The two-way repeated ANOVA is performed to investigate the difference in the groups and period for the metabolic syndrome indicators and the one-way ANOVA and Tukey methods are performed for significant difference. The period difference among the groups is analyzed by the paired t-test. The significance level (α) is configured to 0.05.

RESULTS

Fasting blood sugar changes

The difference in the groups of the subjects with the fasting blood sugar shows that the muscle strengthening exercise using elastic thera-band group significantly decreases from 94.32 mg/dl to 82.11mg/dl after the intervention (p < .001) and the aqua aerobic exercise group significantly decreases from 96.63 mg/dl to 80.74mg/dl after the intervention (p < .001). Also, the combined exercise shows significant decrease from 87.38 mg/dl to 74.38mg/dl after the intervention (p < .001).

The result of the two-way repeated ANOVA for the fasting blood sugar does not show significant difference in the group (F = 2.36, p = .105), time (F = 100.25, p < .001) and interaction according to the group and time (F = 0.70, p = .504) < Table 3>.

Table 3.

Comparisons of fasting blood sugar among three groups

Index	Group	Before	After	t (p)	F (p)
		Mean ± SD	Mean ± SD		Group	Time	Group-time
FBS	Muscle	94.32±14.60	82.11±13.38	-6.79 (<.001)	2.36 (.105)	100.25 (<.001)	0.70 (.504)
	Aquatic	96.63±15.31	80.74±11.66	-6.24 (<.001)
	Combined	87.38±10.31	74.38±9.22	-4.67 (<.001)

Muscle; Muscle strengthening exercise using elastic thera-band, Aqua; Aqua aerobic exercise, Combined; Muscle strengthening exercise using elastic thera-band and aqua aerobic exercise, FBS: Fasting blood sugar

Triglyceride changes

The difference in the triglyceride among the groups shows significant decrease from 152.63mg/dl to 134.00 mg/dl in the muscle strengthening exercise using elastic thera-band group after the intervention (p < .001) and from 145.05mg/dl to 132.11mg/dl after the intervention in the aqua aerobic exercise group (p = .003). Also, the combined exercise shows significant decrease from 167.06mg/dl to 131.19mg/dl after the intervention (p < .001).

The result of the two-way repeated ANOVA for the triglyceride level shows significant difference in the group (F = 0.72, p = .492), time (F = 91.28, p < .001) and interaction according to the group and time (F = 8.67, p < .001) and the triglyceride significantly decreases in the combined exercise group compared to the muscle strengthening exercise using elastic thera-band group and the aqua aerobic exercise group .