Accepted Manuscript
Regular Article
Effects of dynamic stretching in a seated or supine position on blood glucose levels
among young adult women wearing a maternity simulation jacket
Kumiko Ono1*, Mao Nishida2, Junya Okagawa1, Ryoga Yamau1, and Yuto Nakayama1
1

Kobe University Graduate School of Health Sciences, 7-10-2 Tomogaoka, Suma, Kobe,

Hyogo, Japan
2

Kobe University School of Medicine Faculty of Health Sciences, 7-10-2 Tomogaoka,

Suma, Kobe, Hyogo, Japan
Number of tables and figures: 1 and 6
Running title: Dynamic stretch effect on blood glucose during maternity simulation*Corresponding author: onoku@tiger.kobe-u.ac.jp

Abstract
During pregnancy, physiological insulin resistance increases due to endocrine factors
secreted by the placenta. Gestational diabetes mellitus is an example of a common
complication arising from this phenomenon, for which exercise therapy is used as
standard treatment. While the acute effects of static stretching on blood glucose levels are
known, the effects of dynamic stretching in a seated or supine position are unclear. This
study investigated the effects of dynamic stretching in a seated or supine position on blood
glucose levels in young adult women with post-load hyperglycemia wearing a maternity
simulation jacket. We included 11 healthy women in the luteal phase of their menstrual
cycles with blood glucose levels >140 mg/dL 30 min after glucose loading. Four exercise
conditions were established: bed-stretching (BSt) involving dynamic stretching in aseated, supine, or lateral position, standing-stretching (SSt) involving dynamic stretchingin a standing position, walking (W) involving treadmill walking at a comfortable speed,and control (C) involving sitting at rest. After fasting for 10–14 h, blood glucose levels
were measured using self-monitoring blood glucose at baseline and every 15 min for 120
min thereafter. In the BSt and W conditions, the blood glucose levels, peaks, and area
under the curve at 45 and 60 min after glucose loading were significantly lower than thosein the C condition. Therefore, dynamic stretching in a seated or supine position

suppressed blood glucose level elevation after glucose loading in young adult womenwith post-load hyperglycemia wearing a maternity simulation jacket.
Keywords: dynamic stretching, maternity simulation jacket, post-load hyperglycemia

「妊婦体験ジャケットを着用した若年成人女性における臥位または座位での動的ストレッチングが血糖値に及ぼす影響」
小野くみ子 1*、西田眞緒 2、岡川隼也 1、山卯涼我 1、中山優豊 1
1

神戸大学大学院保健学研究科パブリックヘルス領域

2

神戸大学医学部保健学科理学療法学専攻

妊娠時、胎盤から分泌される内分泌因子によって生理的インスリン 抵抗性が亢進される。それによる妊娠合併症の代表例として妊娠糖尿病があり、治療の代表例として運動療法が用いられる。静的ストレッチングの血糖値に対する急性効果は知られているが、座位または臥位での動的ストレッチングの効果は明らかではない。本研究では、座位または臥位での動的ストレッチングの血糖値への影
響を明らかにすることを目的とした。本研究では、妊婦体験ジャケットを着用した負荷後高血糖の若年成人女性において、座位または臥位での動的ストレッチ
ングが血糖値に及ぼす影響を検討した。対象は、月経周期の黄体期にあり、ブドウ糖負荷 30 分後の血糖値が 140mg/dl を超える健康な女性 11 名とした。運動
条件は、座位または臥位で動的ストレッチングを行う BSt 条件、立位で動的ス
トレッチングを行う SSt 条件、快適な速度でトレッドミル歩行を行う W 条件、
安静座位を保持する C 条件の 4 種類とした。10～14 時間の絶食後、ベースライン時およびその後 120 分間 15 分ごとに自己血糖測定法を用いて血糖値を測定した。BSt および W 条件では、グルコース負荷後 45 分および 60 分の血糖値、糖負荷後ピーク血糖値、iAUC が C 条件よりも有意に低かった。したがって、立位、歩行、安静時に比べ、座位または臥位での動的ストレッチングは、妊婦体験
ジャケットを着用した負荷後高血糖の若年成人女性において、ブドウ糖負荷後の血糖値上昇を抑制した。

1

Introduction2

During pregnancy, the placenta secretes various endocrine factors, such as estrogen and3progesterone, that alter autonomic nervous system activity and cellular glucose uptake,4

causing increased heart rate, psychological stress, physiological insulin resistance, and5

postprandial hyperglycemia (1, 2). Gestational diabetes mellitus (GDM) is a typical

6

complication of pregnancy with a global standardized prevalence of 14.7% in the Western

7

Pacific region as of 2021 (3). A meta-analysis evaluating more than 1.3 million

8

individuals reported that the incidence of type 2 diabetes was approximately 10 times

9higher in women with a history of GDM than those with normoglycemic levels (4).

10

Currently, exercise, such as walking or aerobics, is generally recommended to treat

11

GDM and improve hyperglycemia. However, although public health guidelines advise

12that adults engage in 30–150 min of moderate-intensity exercise at approximately 60%

13heart rate reserve (HRR) or 50–60% maximal oxygen uptake (VO₂max) per week, the14rate of achievement remains low (5, 6). Stretching is generally recommended as a form

15

of low-intensity exercise and can be divided into two main categories: static and dynamic.

16

Stretching can be performed in a standing, sitting, or supine position. However, pregnant

17

women are prone to back pain while standing because of uterine expansion and lumbar

18

kyphosis, which shift the center of gravity forward and increases pressure on the lower119

back (7). Reports indicate that habitually implemented stretching performed in a seated20

or supine position can be effective in treating back pain and preventing GDM and21

preeclampsia in pregnant women with sedentary behavior (8, 9). Dynamic stretching22

involves active movements that elongate the target muscle through isotonic contraction

23of the antagonist muscle, whereas static stretching involves holding a stretched position24

for a specific duration. Various studies have addressed the acute effects of static stretching25

on lowering blood glucose after glucose loading (10, 11). The mechanisms by which

26

dynamic stretching improves muscular performance have been suggested to be elevated27

muscle and body temperature, post-activation potentiation in the stretched muscle caused

28

by voluntary contractions of the antagonist, stimulation of the nervous system, and/or

29

decreased inhibition of antagonist muscles (12). Considering these facts, we hypothesized

30

that dynamic stretching may be one of the potential safety exercise therapies that can

31

contribute to the suppression of blood glucose level elevation after glucose loading.

32

Therefore, this study aimed to clarify the effects of dynamic stretching in a seated or

33

supine position on blood glucose levels and compare the effects with those observed while34

sitting at rest, dynamic stretching in a standing position, and walking. Moreover, young

35

adult normoglycemic women were included to provide a basis for proposing an effective

36

exercise regimen for patients with GDM.

2

37
38

Materials and Methods

39

Participants

40

This study included young adult women with a fasting blood glucose level <110 mg/dL

41

and a blood glucose level of ≥140 mg/dL 30 min after consuming 500 mL of a42commercially-available glucose-loaded beverage (200 kcal/50 g carbohydrate/0 g

43protein/0 g fat; Fanta Grape, The Coca-Cola (Japan) Company, Shibuya, Tokyo, Japan).

44

The blood glucose management target for pregnant women with diabetes is to achieve a45

postprandial hourly value of less than 140 mg/dL, and participants were screened for46

possible deviations from the target level (13). Since the purpose of this study was not to47diagnose diabetes, and merely aimed to obtain basic data on non-pregnant healthy women,48

the glucose load was reduced from 75 g with side effects such as nausea to 50g,

49

commercial beverages were used, which are available to everyone. The exclusion criteria

50

were musculoskeletal diseases, comorbid medical conditions, medium- or high-dosage

51

pill (Estrogen-Progesteron) usage, premenstrual syndrome that hinders exercise, and52

irregular menstruation (defined as deviating from the following Japanese Society of

53

Obstetrics and Gynecology criteria: menstrual cycle, 25–38 days; menstruation duration,54

3–7 days). Among the 13 participants screened, 11 met the eligibility criteria and were3

55

included in the study. The participants had a mean age of 22.2±1.0 years, height of56

159.7±5.4 cm, weight of 52.6±5.2 kg, and body mass index (BMI) of 20.6±1.6 kg/m².

57

The full demographic, clinical, and exercise-related characteristics of the participants are

58

shown in Table 1.

59[Insert Table 1 here]60

A sample size of 8 participants was calculated using G*Power 3.1.9.4 (effect size f:

61

0.25, α err prob: 0.05 and Power (1-β err prob): 0.95), but set at approximately 10 to62

account for drop-outs since the participants were asked to take part in the study five times.

63

This study was approved by the Ethics Committee of Health Sciences, Graduate School

64

of Health Sciences, Kobe University (approval no. 1093) and performed in accordance65

with the Declaration of Helsinki. The purpose, content, and risks of the study were fully

66

explained orally and in writing to the participants, and written consent was obtained67

before the study was conducted.

68
69

Study protocol

70

The exercises were performed under the four following conditions after glucose

71

loading: bed-stretching (BSt), in which participants performed dynamic stretching in a72

supine, lateral, or seated position; standing-stretching (SSt), in which participants

4

73

performed dynamic stretching in a standing position; walking (W), in which participants

74

walked on a treadmill at a comfortable speed; and control (C), in which the participants75

remained in a seated resting position. The order of experimentation for the four conditions76

was randomly assigned to each participant using a random number table to conduct a77

randomized crossover study design. Each condition was performed at the same time of78

day on different days, at least two days apart.

79
80

Luteal phase estimation

81

To mimic the hormonal dynamics of gestation, all experimental schedules were82

conducted during the post-ovulatory luteal phase of the participant’s menstrual cycles,

83

when progesterone levels were highest (14). No measurements of various hormone

84

concentrations were taken. The participants underwent daily basal body temperature

85

charting. After determining the point at which the basal body temperature increased after86

a low-temperature phase, which is generally used as an indicator of ovulation, the luteal

87

phase was estimated and the dates of each experiment were scheduled.

88
89

Experimental procedure90

After fasting for a duration of 10–14 h, electrodes were placed on the participant’s chest5

91

and an electrocardiogram was recorded while wearing a maternity simulation jacket (LM-92054; Koken Co., Ltd., Tokyo, Japan) (Fig. 2). Generally, a total of three blood tests,

93

including blood glucose measurements, are performed during antenatal checkups in the94

first, second, and third trimesters of pregnancy. To investigate effective exercises for95

preventing GDM, we selected the mid-pregnancy period, when a higher percentage of96

pregnant women can comfortably ingest food after symptoms such as morning sickness

97

have subsided. In addition, the percentage of high blood glucose levels increases as the98

gestational period progresses, however, the fact that there is no difference in pregnancy

99

and delivery outcomes associated with appropriate interventions, that approximately half

100of those diagnosed with GDM in early pregnancy have no GDM pattern in second

101

trimester, and that the majority of abortions are in first trimester, indicates the importance102

of interventions using physical activity from the middle of pregnancy onwards. Second

103

trimester was set because it was considered to be more important (15, 16). Additionally,104

the weight of the jacket was set to 4.2 kg to reflect mid-pregnancy. Next, the finger-C7

105

distance, which is the distance from the spinous process of the 7th cervical vertebra (C7)106

to the apex of the thumb when the upper limb is rotated from behind and below the trunk,107

was measured in the sitting position, while the knee socket angle was measured in the108

supine position as an index of range of joint motion (ROM). The fasting blood glucose

6

109

level was measured while sitting at rest for 15 min. The degree of lower back pain was

110

assessed using a visual analog scale (VAS). Baseline cardiac parasympathetic nervous

111

system (PNS) activity was also measured by electrocardiography. Then, the designated112

glucose-loaded beverage was consumed over a 10 min period. The rate of perceived

113

exertion (RPE) was measured in the upper extremities, trunk, and lower extremities in the

114

BSt and SSt conditions using the Borg Scale, and after each minute in the W condition.

115

Back pain was measured using the VAS during the rest period between sets. The heart

116

rate was continuously measured during the experiment, and self-monitoring of blood

117

glucose (SMBG) was measured using a blood glucose meter (One Touch Ultra View,

118

LifeScan Japan, Inc., Tokyo, Japan) on nine occasions: immediately before glucose

119

loading and every 15 min after glucose loading for a total of 120 min. Cardiac PNS

120

activity was measured in a sitting position while controlling respiration (inhaling and121

exhaling for 2 s each) using an electronic metronome for 5 min. High-frequency (HF)

122

components of heartbeat variability within 0.15–0.40 Hz were recorded using a real-time

123

heartbeat fluctuation analysis program (MemCalc/Tarawa, Suwa Trust, Tokyo, Japan).

124[Insert Fig. 1 and 2 here]

125

Condition setting

126

The BSt and SSt conditions, each comprising 13 dynamic stretching exercises involving

7

127

the neck, upper limbs, trunk, and lower limbs, were performed at a speed determined by128

a metronome and within each participant’s full ROM as follows: one set of 14 min, a 10-129s rest between stretches, and a 2-min rest between sets. The BSt condition was conducted

130

in a supine, lateral, or end-sitting position on a bed, while the SSt condition was conducted131

in a standing position on a hard surface with a handrail for assistance, if needed. While132

under the W condition, participants walked on a treadmill and were asked to indicate their133

Borg RPE every 1 min. The treadmill walking speed and inclination angle were adjusted

134

to correspond to an RPE of 11 (easy). The C condition involved resting for 30 min in an135

end-sitting position.

136[Insert Fig. 3 here]

137

Statistical analysis

138

All measurements are shown as the mean ± standard deviation, with the exception of139

RPE (median ± standard error). The incremental area under the blood glucose response

140

curve (iAUC) from immediately before and 120 min after the start of glucose loading was

141

calculated using the trapezoidal method. Cardiac PNS activity was calculated as the142natural log-transformed value of the HF (LnHF). Changes in VAS scores were calculated

143

as the difference in back pain during and before the intervention (Δ during intervention)

144

and the difference in back pain after and before the intervention (Δ after intervention).

8

145

Two-way repeated-measures analysis of variance (ANOVA) was performed to146

determine the condition and time effects for blood glucose, LnHF, finger-C7 distance, and147

knee ROM angle <2 h after the start of glucose loading. One-way repeated-measures

148

ANOVA was performed for low VAS change, post-loading peak blood glucose, iAUC,

149

and exercise intensity (%HRR). Mauchly's sphericity test was used to validate the150

ANOVA. If the assumption of sphericity was rejected (p<0.05), the epsilon was adjusted

151

using the Greenhouse–Geisser method. The Holm method was used for post-hoc analysis.

152

All statistical analyses were performed using R for Windows (version 4.1.2; R Core Team,

153

Vienna, Austria). P-values <0.05 were considered statistically significant.

154
155

Results

156

RPE was 11±0.4, 11±0.3, and 11±0.1 in the BSt, SSt, and W conditions, respectively.

157

Exercise intensity (%HRR) was -0.83% in the C condition, 7.84% in the BSt condition,

158

14.7% in the SSt condition, and 21.5% in the W condition (p<0.01, partial η2=0.79,

159

F=36.8, df=10). Regarding exercise intensity, post-hoc analysis revealed that the BSt

160

condition was significantly lower than the SSt and W conditions, the SSt condition was

161

significantly lower than the W condition, and the C condition was significantly lower than162

the other three conditions (all p<0.05).

9

163

The blood glucose levels of all participants are shown in Fig. 4. Under all conditions,164

blood glucose levels increased after the start of glucose loading, peaked at 30 min, and165

decreased until 120 min after the start of glucose loading at the final measurement.

166

Moreover, we found significant differences in the time (p<0.01), condition (p<0.001), and167

interaction (p<0.001, partial η2=0.46, F=8.39, df=24). Regarding blood glucose levels

168

measured after the start of glucose loading, post-test analysis revealed that the BSt

169

condition was significantly lower than the C condition at 30, 45, and 60 min and the W

170

condition at 60 min, the W condition was significantly lower than the C condition at 30,

17145, and 75 min, while the SSt condition was significantly lower at 45 and 60 min than the

172

C condition (all p<0.05).

173[Insert Fig. 4 here]

174

The iAUCs for each condition are shown in Fig. 5. There was a significant difference

175

in the main effect of conditions (p<0.01, partial η2=0.52, F=10.87, df=1.61), with post-176

hoc analysis revealing that the BSt and W conditions were significantly lower than the C

177

condition (p<0.05).

178[Insert Fig. 5 here]179

The post-loading peak blood glucose levels in each condition showed a significant

180

difference in the main effect of conditions (p<0.01, partial η2=0.40, F=6.65, df=3), with

10

181

post-hoc analysis revealing that the BSt (147.4±18.6 mg/dL) and W (142.6±11.4 mg/dL)

182

conditions were significantly lower than the C (171.6±21.1 mg/dL) condition (all p<0.05).

183

No significant inter-condition differences in LnHF were found over time before and184

after the intervention or in the main effect of conditions and interaction effects. The

185changes in VAS scores for back pain under each condition are shown in Figure 6. No

186

significant differences in the main effect of conditions during and after the intervention

187(Δintervention: p=0.12, η²=0.13, F=2.61, df=1.40; Δpost-intervention: p=0.056, η²=0.21,

188

F=4.06, df=1.32) were found.

189[Insert Fig. 6 here]

190

The finger-C7 distance in each condition showed significant differences in the main

191

time and interaction effects (p=0.05, partial η2=0.33, F=4.96, df=2.51), but not in the192

main effect of conditions. Post-test analysis showed a significant increase in ROM from

193

pre-intervention (11.4±4.4 cm) to post-intervention (9.7±3.6 cm) in the BSt condition

194(p<0.05), but not in the SSt condition.

195
196

No significant differences in knee socket angles in each condition over time before andafter the intervention or in main condition and interaction effects were found.

197
198

Discussion

11

199

This study examined the effects of dynamic stretching in a seated or supine position on

200

blood glucose levels in young adult women with post-load hyperglycemia wearing

201

maternity simulation jackets. We found that participants in the BSt condition compared202

to the C condition had significantly lower blood glucose levels at 30, 45, and 60 min after203

glucose loading, blood glucose peaks after glucose loading, and iAUC (p<0.05). These

204

results are similar to those obtained in the W condition. Postprandial hyperglycemia and205

blood glucose spikes <2 h after consuming food are considered risk factors for

206

cardiometabolic disorders not only in patients with diabetes, but also in healthy

207

individuals (17, 18, 19). The present study showed that exercising under the BSt condition

208

could effectively resolve post-load glucose spikes and reduce the increase in blood

209

glucose within 120 min after glucose loading compared with the controls. In contrast, the210

iAUC and blood glucose levels at 60 min after initiating glucose loading were not211

significantly different in the SSt condition than those in the C condition. During acute212

exercise or stretching, skeletal muscle contraction causes glucose transporter 4 (GLUT4)213

translocation to the plasma membrane (20) and activates insulin-independent glucose

214

transport, ultimately promoting glucose uptake and improving glycemic control (11, 21).

215

The reason why the blood glucose trend was significantly higher at the end of the exercise

216(45 minutes) compared to the BSt condition is that the exercise intensity was significantly

12

217

higher in the W condition than in the other conditions, although the RPE was the same218

(in terms of perception), and the load applied to the front of the trunk required the219

participant to contract muscles that would not contract in the non-pregnant state, this may

220

be due to the higher heart rate induced by catecholamines and the increase in blood

221

glucose induced by glucocorticoids (22). The BSt condition showed significantly

222

improved ROM before and after the intervention compared to the finger intervertebral

223

distance, suggesting stretching of the target muscle, accompanied by contraction of the224

antagonist muscle. In contrast, the SSt condition showed no significant difference in pre-225

and post-intervention finger-C7 distance, and the stretching effect of correcting blood226

glucose levels was lower than that of the BSt condition. Reports indicate that dynamic

227

balance in the standing position is reduced when wearing a maternity simulation jacket

228(23); thus, instability may have impacted ROM while stretching under the SSt condition.

229
230

Although there were no significant inter-condition differences in VAS scores, there was231

a trend towards reduced back pain after exercise in the BSt condition (Δ post-intervention

232

effect size, η²=0.21). Because back pain can hinder physical activity engagement,

233

exercising under the BSt condition may be easily adopted during pregnancy to promote234

good exercise habits.

13

235

No significant differences were observed in LnHF, a stress indicator of cardiac PNS

236

activity, either over time or between conditions. Although there are examples of enhanced

237

PNS activity after static stretching and yoga, Farinatti et al. (24) reported that PNS activity

238

in individuals with low flexibility and isometric antagonist muscle contractions during

239

static stretching did not differ significantly before and after the intervention. Moreover,240

Michael et al. (25) found that PNS activity recovery was delayed after high-intensity

241

exercises and was not significantly different before and after the intervention in pregnant

242

women. Low-intensity exercise that does not decrease PNS activity may be beneficial to243

reduce stress in pregnant women, whose PNS activity tends to be suppressed due to244

hormonal changes.

245

These findings suggest that dynamic stretching in a seated or supine position

246

significantly reduced blood glucose levels in young adult women wearing a maternity

247

simulation jacket with post-load hyperglycemia more than when resting, sitting, and248

walking. Moreover, stretching in this position improved glycemic control, tended to249

reduce back pain, and suppressed PNS activity.

250
251

This study has some limitations. First, since the participants were young adult non-

252

pregnant women, their condition differed from the hormonal dynamics of pregnancy, and

14

253

the results were limited to blood glucose variability during frontal trunk loading. Second,254

VO₂max and energy expenditure were not measured using expiratory gas analysis; hence,

255

exercise intensity was not matched across conditions, making it difficult to examine and256

directly compare the effects of exercise on blood glucose correction. Lastly, blood glucose

257

data were obtained by SMBG using a glucometer and sensor, which have a specific258

margin range of error. Therefore, future studies with larger sample sizes should be259

conducted to validate the results of this study, as well as those examining the effects of260

different energy expenditure-matched exercise modalities on blood glucose correction261

and of dynamic stretching in both normo- and hyperglycemic pregnant women.

262This study found that dynamic stretching in a seated or supine position significantly

263

reduced blood glucose levels and blood glucose peaks within 120 min after glucose

264

loading in young adult women with post-load hyperglycemia wearing a maternity

265

simulation jacket during the luteal phase of their menstrual cycle. This suggests that266

dynamic stretching in a seated or supine position is superior to exercising while standing

267

and walking in terms of lowering back pain and controlling blood glucose levels in young

268

hyperglycemic women. These findings may also provide a basis for proposing an269

effective exercise regimen for patients with GDM.

270

15

271

Contributions

272

OK conceptualized the research design and protocol, and carried out the interpretation of273

data. NM conceptualized the study design and protocol, collected and assembled the data,274

and carried out the analysis and interpretation of data. OJ, YY, and YR collected and275

carried out the interpretation of data. OK and NM drafted the manuscript. All authors

276

have critically reviewed, revised, and approved the manuscript.

277
278

Clinical trial registration

279

This study was registered with the University Hospital Medical Information Network

280(UMIN) Clinical Trials Registry (registration number: UMIN000052137).

281
282

Conflict of Interest

283

All authors declare that there is no conflict of interests regarding the publication of this284

article.

285
286

Acknowledgements

287

We thank all those who participated in the experiments.

16

288

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364

Figure Legends

365

Fig. 1: Study details and protocols.

366

Fig. 2: The maternity simulation jacket.

367

Fig. 3: Blood glucose level measurements from immediately before glucose loading368

to 120 min after the start of glucose loading.

369

Blood glucose levels in the bed-stretching (BSt) condition is significantly lower than370

those of the control (C) condition at 30, 45, and 60 min after glucose loading.

371

Fig. 4: Area under the elevated blood glucose concentration curve 120 min after

372

glucose loading.

373

Blood glucose levels in the bed-stretching (BSt) and walking (W) conditions are374

significantly lower than those of the C conditions.

375

Fig. 5: Changes in visual analog scale (VAS) scores from baseline back pain levels.

376(A) showed intervention phase. (B) showed after intervention phase. The bed-stretching

377(BSt) condition shows a decreasing trend, but is not significantly different than the other378

conditions.

379
380
381

22

382

Tables383

Table 1. Characteristics of participants under each condition.

384

23

Fig. 1: Study details and protocols

Fig. 2: The maternity simulation jacket

d)(100 bpm)

Pectoralis
Major

Biceps(100 bpm)d)b)

4 dynamic stretching exercisesc)a)

4 dynamic stretching exercises(100 bpm)

Scapulab)(45 bpm)

Trapezius

c)

Trunk

a)

Trunk

Neck/ Upper Limb

Neck/ Upper Limb

Bed-StretchingStanding-Stretchinge)(100 bpm)(100 bpm)g)

4 dynamic stretching exercisesf)h)Gluteus medius/
Oblique Abdominals(100 bpm)

Latissimus Dorsi/
Oblique Abdominals(100 bpm)h)f)

4 dynamic stretching exercises

Gluteus Maximus/Erector Spinaeg)

Rectus Abdominis/Erector Spinaee)Fig. 3: Description of the stretching condition

Lower Limb
Lower Limb

i)

j)

i)

j)

Adductor(70 bpm)l)

5 dynamic stretching exercisesk)

5 dynamic stretching exercises(70 bpm)

Adductor/
Hamstrings(70 bpm)

Quadriceps
femorisk)(70 bpm)(70 bpm)m)

Triceps Surae/
Tibialis Anteriorm)

Hamstrings/
Gluteus Maximusl)Fig. 4: Blood glucose level measurements from immediately before
glucose loading to 120 min after the start of glucose loading

Repeated measures
two-way ANOVA
conditions：p＜0.01
times：p＜0.001
interactions：p＜0.001* :p<0.05 vs C
† :p<0.05 vs W

Fig. 5: Area under the elevated blood glucose concentration
curve 120 min after glucose loading.

Fig. 6: Changes in visual analog scale (VAS) scores frombaseline back pain levels.
Repeated measures one-way ANOVA
Δ intervention: not significant
effect size η2＝0.13(A)
Repeated measures one-way ANOVA
Δ after intervention: p＜0.05
post-hoc test: not significant
effect size η2＝0.21(B)