Chronic Exercise Group Research Articles

Sheng Zhen Gong in pregnancy: The effects of a traditional low intensity exercise form on maternofetal health and wellbeing

Objective: The aim of the study was to evaluate maternal and fetal responses to Sheng Zhen Gong (SZG), a low intensity form of exercise, using multi-modal antenatal surveillance techniques. Methods: This was a single-blinded randomized controlled trial in low risk pregnant women from a tertiary center in the Philippines. Participants were randomized into Chronic Exercise (CE), Acute Exercise (AE) and No Exercise (NE) groups. A Pregnancy Physical Activity Questionnaire (PPAQ) was given to ascertain baseline activities. Systematic periodic assessment was performed utilizing standard ultrasound and Doppler studies between 20+0 to 32+0 weeks gestation with or without sessions involving a biophysical and Warwick-Edinburgh Mental Well-being Scale (WEMWBS) evaluation before and after SZG exercise. Results: Eighty-nine (89) women were included with average energy expenditures of light to moderate intensity. In the CE group, systolic, diastolic, mean arterial pressures and heart rates were lower while oxygen saturations increased after exercise (n=35; p: <0.01 to 0.01). There were also observable significant increases in maternal well-being scores after exercise for both CE (n=35) and AE (n=21) groups (p<0.01). Increasing the frequency of exercise was also associated with better maternal well-being (p: 0.02). Fetal Doppler studies showed no significant changes after exercise. Conclusion: In normal pregnancy, routine low intensity physical activity in the form of SZG was seen to have positive effects on maternal cardiovascular, blood glucose and mental well-being maintenance with no evidence of detrimental effects on the fetus.

Effects of acute and chronic exercise on fat PI3K/AKT/GLUT4 signal pathway in type 2 diabetic rats

To study the effects of acute and chronic exercise on phosphatidylinositol 3-hydroxy kinase(PI3K)/protein kinase B(AKT)/glucose transporter 4(GLUT4)signaling pathway in adipose tissue of rats with type 2 diabetes mellitus (T2DM) induced by high-fat diet and low-dose streptozotocin (STZ). A total of 52 SD male rats aged 15 months were randomly divided into normal control group (13) and high-fat group (39), and fed normal and high fat diets. After 8 weeks, the body weight of the high-fat group was higher 20% than that of the normal control group. After a small dose of STZ, the blood glucose level was ＞16.7 mmol/l, and the model was successfully established. The diabetic model group was randomly divided into a diabetic control group (DC, n=13), a diabetic chronic exercise group (DCE, n=13), and a diabetic acute exercise group (DAE, n=13). The DCE group underwent an 8-week swimming exercise and the DAE group performed a one-time swimming exercise. Blood lipids, blood glucose and serum insulin levels were measured, and the contents of fat PI3K, AKT and GLUT4 proteins were determined by Western blot method. The levels of body weight, blood lipids, blood glucose and insulin in the diabetic group were significantly higher than those in the normal control group (P＜0.01); high density liptein cholesterol(HDL-C) levels were decreased (P＜0.05), and the expressions of PI3K, AKT and GLUT4 protein in adipose tissue were decreased (P＜0.01). After 8 weeks of swimming training, the levels of body weight, blood lipids, blood glucose and insulin all were decreased significantly (P＜0.01); while the level of HDL-C was increased (P＜0.05), and the expressions of PI3K, AKT and GLUT4 protein were increased (P＜0.01). After acute exercise, the levels of blood lipids, blood glucose and insulin were decreased (P＜0.05); the level of HDL-C was increased (P＜0.05), and the expression levels of fat PI3K, AKT and GLUT4 were increased significantly (P＜0.05). ①High fat diet combined with low-dose STZ induced damage to the PI3K/AKT pathway in adipose tissue of T2DM rats reduced insulin sensitivity. ②Acute and chronic aerobic exercise can improve the disorder of glucose and lipid metabolism through PI3K/AKT pathway, and the chronic exercise is better than acute exercise.

A comparative study on the effects of acute and chronic downhill running vs uphill running exercise on the RNA levels of the skeletal muscles PGC1-α, FNDC5 and the adipose UCP1 in BALB/c mice

The purpose of this study was to investigate the effect of a single bout and 8 weeks of downhill running versus uphill running exercise on expression of PGC1-α, FNDC5 and UCP1 in mice. Forty-eight BALB/c male mice weighing 25–30 g were randomly assigned into 8 groups: 1) acute downhill running (ADR) on a −15° slope; 2) acute uphill running (AUR) on a +15° slope; 3) acute running without inclination (AWI), 4) acute without exercise as control (ACtrl), 5) chronic downhill running (CDR) on a −15° slope; 6) chronic uphill running (CUR) on a +15°slope; 7) chronic running without inclination (CWI), 8) chronic without exercise as control (CCtrl). Twenty four hours after the last training session, the mice were sacrificed and Calf muscles (including soleus and gastrocnemius) and quadriceps muscles (including Rectus femoris and vastus intermedius) were obtained and expression levels of PGC1-α and FNDC5 in crus and quadriceps muscles and UCP1 in visceral and subcutaneous adipose tissues were measured and compared between the groups. PGC-1α and FNDC5 mRNA levels increased after treadmill exercise training in all acute and chronic exercise groups in both skeletal muscle groups. Furthermore mRNA level of UCP1 in subcutaneous adipose tissue but not in visceral adipose tissue increased both after acute and chronic exercise. Collectively, data showed that downhill running exercise to be more effective than other exercises, as downhill running has led to a greater improvement in metabolism may be considered more effective for browning of fat tissue.

Doxycycline improves cage activity, but not exercised, supraspinatus tendon and muscle in a rat model

The objective of this study was to investigate the effects of doxycycline, a broad-spectrum MMP inhibitor, on cage activity and exercised supraspinatus tendon and muscle using a Sprague-Dawley rat model of non-injurious exercise. Because exercise may alter muscle and tendon MMP activity and matrix turnover, we hypothesized that doxycycline would abolish the beneficial adaptations found with exercise but have no effect on cage activity muscle and tendon properties. Rats were divided into acute or chronic exercise (EX) or cage activity (CA) groups, and half of the rats received doxycycline orally. Animals in acute EX groups were euthanized 24 h after a single bout of exercise (10 m/min, 1 h) on a flat treadmill. Animals in chronic EX groups walked on a flat treadmill and were euthanized at 2 or 8 week time points. Assays included supraspinatus tendon mechanics and histology and muscle fiber morphologic and type analysis. Doxycycline improved tendon mechanical properties and collagen organization in chronic cage activity groups, which was not consistently evident in exercised groups. Combined with exercise, doxycycline decreased average muscle fiber cross-sectional area. Results of this study suggest that administration of doxycycline at pharmaceutical doses induces beneficial supraspinatus tendon adaptations without negatively affecting the muscle in cage activity animals, supporting the use of doxycycline to combat degenerative processes associated with underuse; however, when combined with exercise, doxycycline does not consistently produce the same beneficial adaptations in rat supraspinatus tendons and reduces muscle fiber cross-sectional area, suggesting that doxycycline is not advantageous when combined with activity.

Effect of acute and chronic exercise on plasma matrix metalloproteinase and total antioxidant levels.

The relationship between acute and chronic exercise and expression of matrix metalloproteinases (MMPs) in muscles is unknown. There happen some alterations in the oxidant-antioxidant balance due to exercise. This study aimed to investigate the levels of MMP-1, tissue inhibitors of metalloproteinases (TIMP-1), hyaluronic acid (HA), total antioxidant status (TAS), and total oxidant status (TOS) following acute and chronic exercising in rats. Twenty-six Wistar Albino male rats were divided in to three groups: control, acute, and chronic groups. In acute group, treadmill exercise was performed 3 days/wk, 10 min/day for 1 week. In chronic group, exercise performed 7 days/wk, 60 min/day for 4 weeks. At the end of the experiment, plasma MMP-1, TIMP-1, HA, TAS, and TOS levels were measured. In current study, the MMP-1, TIMP-1, HA, and TOS levels not observed statistically significant difference among all groups, but in chronic group, there was a significantly difference (P<0.05) between the control and experimental groups in terms of TAS and oxidative stress index (OSI) levels. TAS, TOS, and OSI levels were significantly different between control and chronic exercise group (P<0.01, P<0.05, and P<0.01, respectively). According to these results, we can say acute and chronic exercise does not effect on plasma MMP-1, TIMP-1, and HA levels.

Rat supraspinatus tendon responds acutely and chronically to exercise.

The objective of this study was to identify acute responses and chronic adaptations of supraspinatus tendon to noninjurious exercise. We hypothesized that chronic exercise (EX) increases tendon mechanical properties, and a single exercise bout increases matrix metalloproteinase (MMP) activity acutely. Rats were divided into acute or chronic EX or cage activity groups. Animals in acute EX groups were euthanized, 3, 12, 24, 48, or 72 h upon completion of a single bout of exercise (10 m/min, 1 h) on a flat treadmill. Animals in chronic EX groups walked on a flat treadmill for 3 days or 1, 2, or 8 wk. Tendon histology, MMP activity, and mechanics were measured. A single bout of exercise trended toward reducing tendon mechanical properties, but 2 or 8 wk of chronic EX increased tendon mechanics. Cell density was not affected. Cells became rounder with chronic EX. All tendons were highly organized. MMP activity decreased after a single bout of exercise and returned to baseline by 72 h. MMP activity decreased after 8 wk of chronic EX. Decreased MMP activity may indicate an anabolic instead of catabolic response in contrast to injury. Results suggest that mild, acute decreases in MMP activity and tendon mechanics following a single exercise bout lead to enhanced tendon mechanical adaptations with repeated exercise bouts. This study defines acute and chronic changes of MMP activity, mechanical properties, and histology of the rat supraspinatus tendon in response to beneficial exercise and proposes a mechanism by which acute responses translate to chronic adaptations.NEW & NOTEWORTHY The line between beneficial exercise and overuse has not been elucidated. This study defines the acute and chronic temporal response to exercise of supraspinatus tendon in an in vivo model. We found that decreased matrix metalloproteinase activity and tendon mechanics after a single bout of exercise are followed by beneficial chronic adaptations of the tendon with repeated bouts. How the acute responses to exercise lead to chronic adaptations may distinguish beneficial exercise from overuse.

Examination of levels pentraxin-3, interleukin-6, and C-reactive protein in rat model acute and chronic exercise.

Different types of exercise occurs damage at the cellular level in the muscles. Muscle damage caused by exercise is determined creatine kinase, myoglobin, and increase in levels of acute phase protein and interleukin in blood. The purpose of this study was investigated the levels of pentraxin-3 (PTX-3), interleukin-6 (IL-6), and C-reactive protein (CRP) following acute and chronic exercising in rats. Twenty-six Wistar Albino male rats were divided in to three groups. A treadmill exercise was performed 3 days/week, 10 min/day for 1 week in acute groups. In chronic group, exercise performed 7 days/week, 60 min/day for 4 weeks. At the end of the experiment, plasma PTX-3, IL-6, and CRP levels were measured. In current study, the PTX-3, IL-6, and CRP levels not observed statistically significant difference among control, acute, and chronic groups. The levels IL-6 and CRP were not significantly different between acute and chronic exercise groups (P>0.05). However, the level of PTX-3 was found to be higher in the chronic group compared to the acute group (P<0.05). The PTX-3 level increase on chronic exercise-induced muscle damage. Accorting to our results, we think that PTX-3 may have a protect role on muscle damage during chronic exercises.

Continuous Aerobic Training in Individualized Intensity Avoids Spontaneous Physical Activity Decline and Improves MCT1 Expression in Oxidative Muscle of Swimming Rats.

Although aerobic training has been shown to affect the lactate transport of skeletal muscle, there is no information concerning the effect of continuous aerobic training on spontaneous physical activity (SPA). Because every movement in daily life (i.e., SPA) is generated by skeletal muscle, we think that it is possible that an improvement of SPA could affect the physiological properties of muscle with regard to lactate transport. The aim of this study was to evaluate the effect of 12 weeks of continuous aerobic training in individualized intensity on SPA of rats and their gene expressions of monocarboxylate transporters (MCT) 1 and 4 in soleus (oxidative) and white gastrocnemius (glycolytic) muscles. We also analyzed the effect of continuous aerobic training on aerobic and anaerobic parameters using the lactate minimum test (LMT). Sixty-day-old rats were randomly divided into three groups: a baseline group in which rats were evaluated prior to initiation of the study; a control group (Co) in which rats were kept without any treatment during 12 weeks; and a chronic exercise group (Tr) in which rats swam for 40 min/day, 5 days/week at 80% of anaerobic threshold during 12 weeks. After the experimental period, SPA of rats was measured using a gravimetric method. Rats had their expression of MCTs determined by RT-PCR analysis. In essence, aerobic training is effective in maintaining SPA, but did not prevent the decline of aerobic capacity and anaerobic performance, leading us to propose that the decline of SPA is not fully attributed to a deterioration of physical properties. Changes in SPA were concomitant with changes in MCT1 expression in the soleus muscle of trained rats, suggestive of an additional adaptive response toward increased lactate clearance. This result is in line with our observation showing a better equilibrium on lactate production-remotion during the continuous exercise (LMT). We propose an approach to combat the decline of SPA of rats in their home cages. This new finding is worth for scientists who work with animal models to study the protective effects of exercise.

Effects of Grape Seed Polyphenols on Oxidative Damage in Liver Tissue of Acutely and Chronically Exercised Rats

The objective of the present study was to investigate the effects of grape seed extract (GSE) supplementation on oxidative stress and antioxidant defense markers in liver tissue of acutely and chronically exercised rats. Rats were randomly assigned to six groups: Control (C), Control Chronic Exercise (CE), Control Acute Exercise (AE), GSE-supplemented Control (GC), GSE-supplemented Chronic Exercise(GCE) and GSE-supplemented Acute Exercise (GAE). Rats in the chronic exercise groups were subjected to a six-week treadmill running and in the acute exercise groups performed an exhaustive running. Rats in the GSE supplemented groups received GSE (100 mg.kg(-1) .day(-1) ) in drinking water for 6 weeks. Liver tissues of the rats were taken for the analysis of malondialdehyde (MDA), nitric oxide (NO) levels and total antioxidant activity (AOA) and xanthine oxidase (XO) activities. MDA levels decreased with GSE supplementation in control groups but increased in acute and chronic exercise groups compared to their non-supplemented control. NO levels increased with GSE supplementation. XO activities were higher in AE group compared to the CE group. AOA decreased with GSE supplementation. In conclusion, while acute exercise triggers oxidative stress, chronic exercise has protective role against oxidative stress. GSE has a limited antioxidant effect on exercise-induced oxidative stress in liver tissue.

Chronic training increases blood oxidative damage but promotes health in elderly men

The objective of the present study was to investigate a large panel of oxidative stress biomarkers in long-term trained elderly men to analyse the effects of chronic training on an aged population. We collected blood samples from two groups of male volunteers older than 65 years who maintain a measure of functional independence: one group of sedentary subjects without a history of regular physical activity and the other of subjects who have sustained training, starting during middle age (mean training time=49 ± 8 years). We studied morbidity and polypharmacy, as well as haematological parameters including red cell count, haemoglobin concentration, haematocrit, mean corpuscular volume, red cell distribution width and several oxidative biomarkers including protein carbonyl content and lipid peroxidation in plasma and erythrocytes, red blood cell H2O2-induced haemolysis test, plasma total antioxidant activity and the main antioxidant enzymes of erythrocytes: superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase. After adjusting for confounding factors, we observed an increase in all oxidative damage biomarkers in the plasma and erythrocytes of the long-term exercise group. However, we reported a decrease in the number of diseases per subject with statistical differences nearly significant (p=0.061), reduced intake of medications per subject and lower levels of red cell distribution width in the chronic exercise group. These results indicate that chronic exercise from middle age to old age increases oxidative damage; however, chronic exercise appears to be an effective strategy to attenuate the age-related decline in the elderly.

Effects of grape seed extract supplementation on exercise-induced oxidative stress in rats

The aim of the present study was to investigate the effects of grape seed extract (GSE) supplementation on exercise performance and oxidative stress in acutely and chronically exercised rats. A total of sixty-four male rats were used in the study. Rats were divided into six groups: control, chronic exercise control, acute exercise control (AEC), GSE-supplemented control, GSE-supplemented chronic exercise and GSE-supplemented acute exercise groups. Chronic exercise consisted of treadmill running at 25 m/min, 45 min/d, 5 d a week for 6 weeks. Rats in the acute exercise groups were run on the treadmill at 30 m/min until exhaustion. GSE were given at 100 mg/kg of body weight with drinking water for 6 weeks. Plasma was separated from blood samples for the analysis of oxidative stress markers. There was no significant difference in time of exhaustion between the acute exercise groups. Plasma malondialdehyde (MDA) levels were higher in the acute exercise groups and lower in the chronic exercise groups. GSE supplementation decreased MDA levels. Xanthine oxidase and adenosine deaminase activities were higher in the AEC group compared to all the other groups. NO levels were increased with both chronic exercise and GSE supplementation. Superoxide dismutase and glutathione peroxidase activities were lower in the acute exercised groups and higher in the chronic exercised groups. GSE supplementation caused an increase in antioxidant enzyme activities. In conclusion, GSE supplementation prevents exercise-induced oxidative stress by preventing lipid peroxidation and increasing antioxidant enzyme activities.

Effect of Acute and Chronic Physical Exercise on Patients with Periodic Leg Movements

Nonpharmacological interventions may lead to an improvement in sleep quality. The objective of our study was to evaluate the effects of acute intensive exercise and chronic exercise on sleep patterns in patients with periodic leg movements (PLM). The study involved acute and chronic exercise. The acute intensive exercise group consisted of 22 volunteers who underwent a maximum effort test and a polysomnography (PSG) on the same night. The chronic exercise group included 11 patients who performed 72 physical training sessions undergoing three PSG studies on the night of sessions 1, 36, and 72. Blood samples were collected from both acute and chronic groups for beta-endorphin dosage. Our results showed that both forms of physical exercise lowered PLM levels. The acute physical exercise increased sleep efficiency, rapid eye movement (REM) sleep, and reduced wake after sleep onset, whereas the chronic physical exercise increased sleep efficiency, REM sleep, and reduced sleep latency. We also found a significant negative correlation between beta-endorphin release after acute intensive exercise and PLM levels (r = -0.63). Physical exercise may improve sleep patterns and reduce PLM levels. The correlation between beta-endorphin release after acute intensive exercise and PLM levels might be associated with the impact physical exercise has on the opiodergic system. We suggest that physical exercise may be a useful nonpharmacological treatment for PLM.

Adiponectin Oligomers in Human Serum during Acute and Chronic Exercise: Relation to Lipid Metabolism and Insulin Sensitivity

Beneficial effects of physical exercise include improved insulin sensitivity, which may be affected by a modulated release of adiponectin, which is exclusively synthesized in white adipose tissue and mediates insulin sensitivity. Adiponectin circulates in three different oligomers, which also have a distinct biological function. We therefore aimed to investigate the distribution of adiponectin oligomers in human serum in relation to physical activity. Thirty-eight lean and healthy individuals were investigated. Seven healthy women and 8 healthy men volunteered to investigate the effect of chronic exercise, at 3 different time points with different training intensities. These individuals were all highly trained and were compared to a control group with low physical activity (n = 15). For studying acute exercise effects, 8 healthy men participated in a bicycle test. Adiponectin was determined by ELISA, oligomers were detected by non-denaturating western blot. Total adiponectin and oligomers were unchanged by acute exercise. LDL cholesterol was significantly lower in the chronic exercise group (p = 0.03). Total adiponectin levels and oligomers were not different between these two groups and were unaltered by different training intensities. However, total adiponectin and specifically HMW oligomers correlated with HDL cholesterol (r = 0.459; p = 0.009). We conclude that acute and chronic exercise does not directly affect circulating adiponectin or oligomer distribution in lean and healthy individuals. Whether such regulation is relevant in individuals with a metabolic disorder remains to be determined. However, our data suggest that adiponectin oligomers have distinct physiological functions IN VIVO, and specifically HMW adiponectin is closely correlated with HDL cholesterol.

Chronic exercise and the pro-inflammatory response to endotoxin in the serum and heart

Purpose: To examine the effects of moderate intensity chronic exercise on tumor necrosis factor-alpha (TNFα) and inducible nitric oxide synthase (iNOS) responses to endotoxin in female Sprague-Dawley rats. Methods: Rats were divided into two groups, exercise ( n = 17) and sedentary ( n = 24). Exercise (Ex) rats completed 12 weeks of motorized treadmill running 3 days/week for 15–25 min at 22–25 m/min, while sedentary (Sed) rats remained in their cages. Twenty-four hrs after the last exercise session, animals were subdivided into three groups. One subgroup served as baseline controls. These rats received an injection of saline (s) and were killed immediately (Sed-s and Ex-s), while the other groups received an injection of lipopolysaccharide (LPS). LPS animals were killed 2 h (Sed-L2 and Ex-L2) or 4 h after the LPS injection (Sed-L4 and Ex-L4). Results: Serum TNFα was elevated 2 h after LPS injection in both Sed and Ex groups, but was significantly higher in the chronic exercise group (Ex-L2 versus. Sed-L2). Similarly, serum β glucuronidase activity, an indicator of tissue damage, was elevated 2 and 4 h after LPS injection, and was significantly higher in the exercise groups. Post-treatment left ventricular TNFα and iNOS activity, as well as stable nitric oxide derivatives in the serum (NO x ), were significantly higher in LPS-injected groups compared to saline groups, but no difference in LPS effect was observed between sedentary and exercise groups. Conclusions: Moderate intensity chronic exercise stress caused an exaggerated serum TNFα response to endotoxin and an elevation in a serum marker of LPS-induced tissue damage.

Long-lived Ames dwarf mouse exhibits increased antioxidant defense in skeletal muscle

Resting and exercised (both acute and chronic) hindlimb skeletal muscle from long-lived Ames dwarf and wild type mice at 3, 12, 18, and 24 months of age was tested for antioxidant enzyme activity and protein, non-enzymatic antioxidant ratios, mitochondrial hydrogen peroxide concentration, and plasma lactate levels. Differences were observed in GPX enzyme activity between mouse genotypes at all physical activity levels, with dwarf mice exhibiting depressed levels at younger ages (3 months: P=0.09 [non-swim], P=0.03 [acute swim], P=0.04 [chronic swim]) and comparatively higher levels than wild type mice at older ages (18–24 months: P=0.05 [acute swim], P=0.07 [chronic swim]). Catalase enzyme activity and the GSH system rarely demonstrated significant differences between genotypes, regardless of age or activity. However, the chronic exercise group displayed a difference in GSH:GSSG ratios between mouse genotypes ( P=0.005). Plasma lactate concentrations were elevated in the wild type mice compared to the dwarf mice at all ages in all activity groups. These results suggest there are biological differences with regard to antioxidant defense that favor the Ames dwarf mouse in active and resting skeletal muscle when compared to wild type mice.

Effect of physical exercise on kindling development.

The relationship between epilepsy and exercise is a subject of controversy and needs more investigation. We report a study of the effect of physical activity on the development of amygdala kindling in rats. To analyze the acute and chronic effects of exercise on kindling development, 45 rats were divided randomly into three groups. The first group (acute group, n=15) was submitted to a daily bout of aerobic exercise (40 min running on the treadmill at 20 m/min) and kindling stimulated 1 min post-exercise; the second group (chronic group, n=15) was submitted to an aerobic training program (40 min running on the treadmill at 20 m/min, 7 days per week, for 45 days) and then submitted to the same procedure as the first group (daily bout of aerobic exercise -- 40 min running on the treadmill at 20 m/min and kindling stimulated 1 min post-exercise); and the third group (n=15) served as control. All groups were kindling stimulated until they reached stage 5 of kindling. The number of stimulations required to reach stage 5 was statistically higher for the chronic exercise group when compared to the acute exercise group and the control group. A longer time spent in stage 1 and a shorter after-discharge duration in stage 1 was observed in the acute and chronic exercise groups in relation to the control group. This finding suggests that chronic physical exercise inhibits development of amygdala kindling in rats.

The Effects of Swimming Exercise on Adrenal Gland Weight and the Differential Count of Peripheral Blood in Albino Rats

The effects of acute and chronic swimming exercise on leukocyte counts, the cortisole level, and the thymus, spleen and adrenal glands were studied in 30 female albino rats. There were 10 animals in each of three groups: the control, acute and chronic exercise groups. The test rats in the acute group were made to swim for ten minutes those in the chronic group, 10 minutes a day for 8 days. Total white blood cell (WBC) counts, differential counts and the weights of the thymus, spleen and adrenal glands were measured. In the acute exercise group, the WBC, lymphocyte, neutrophil and monocyte counts and the ratios of adrenal gland weight/body weight were lower than those in the control group (P