This work aimed to study the effect of swimming exercise on serum vitamin D level and tissue vitamin D receptors in experimentally induced type 2 Diabetes Mellitus. Sixty adult male rats were divided into control and diabetic groups. Each was further subdivided into sedentary and exercised subgroups. Diabetes Mellitus was induced by a single intraperitoneal dose of streptozotocin (50 mg/kg) dissolved in cold 0.01 M citrate buffer (pH 4.5). The exercised subgroups underwent swimming for 60 min, 5 times a week for 4 weeks. Serum glucose, insulin, homeostasis model assessment of insulin resistance (HOMA-IR), lipids, vitamin D and tissue Vitamin D receptors (VDR) were evaluated. Significant increase in serum glucose, insulin, HOMA-IR, cholesterol, triglycerides, and low density lipoprotein (LDL) levels in sedentary diabetic rats was detected. On the other hand, high density lipoprotein (HDL), free fatty acids, serum vitamin D and pancreatic, adipose, and muscular VDR showed a significant decrease in the same group. It is evident that all these parameters were reversed by swimming exercise indicating its beneficial role in type 2 Diabetes. In diabetic groups; serum vitamin D was found to be correlated negatively with serum glucose, insulin, HOMA, cholesterol, triglycerides, and LDL and positively correlated with HDL and tissue VDR. In conclusion, Disturbed vitamin D is associated with metabolic impairments in sedentary diabetic rats. Moderate swimming exercise is beneficial in improving these consequences through modulation of vitamin D status. Future studies could be designed to investigate the effect of the combination of vitamin D intake with exercise in diabetic patients.

Antrodia camphorata and Panax ginseng are well-known medicinal plants in Taiwan folk and traditional Chinese medicine, which have been reported for multifunctional bioactivities. However, there is limited evidence that a fixed combination formula of these two plant extracts is effective for the exercise improvement or anti-fatigue. We aimed to evaluate the potential beneficial effects of the mix formulation of these two herbal medicines (AG formulation) on fatigue and ergogenic functions following physiological challenge. Male Institute of Cancer Research (ICR) mice from four groups (n=10 per group) were orally administered AG formulation for 4 weeks at 0.984, 2.952 and 5.904 g/kg/day, which were designated the Vehicle, AG-1X, AG-3X and AG-6X groups, respectively. The anti-fatigue activity and exercise performance were evaluated using exhaustive swimming time, forelimb grip strength, and levels of serum lactate, ammonia, glucose, blood urea nitrogen (BUN) and creatine kinase (CK) after a swimming exercise. The exhaustive swimming time of the 1X, 3X or 6X AG group was significantly longer than that of the Vehicle group, and the forelimb grip strength of the 1X, 3X or 6X AG group was also significantly higher than that of the Vehicle group. AG supplementation also produced decreases in serum lactate, ammonia, BUN and CK activity after the swimming test, as well as increases in glucose. Therefore, the AG complex could be a potential formulation with an anti-fatigue pharmacological effect.

BACKGROUND:To determine the effects of probiotic yogurt on performance and health status of young adultfemale endurance swimmers.

METHODS:In a randomized controlled trial, 46 endurance swimmers girls with mean age of 13.8±1.8 years,weight of 48.6±7.5kg and height of 159±5.6cm, were studied. Subjects were randomly assigned into two groups,receiving either 400 ml probiotic yogurt (intervention group) or ordinary yogurt (control group) daily for 8weeks. At the beginning and at the end of the study, the 400-m free swimming record was done and the HarvardStep test was employed to measure VO2max. Statistical analysis of the data was performed using SPSS software.This trial has been registered with IRCT ID of IRCT2012122311849N1.

RESULTS:Average changes in the records of the intervention and control groups were 3.9 and 0.5 seconds, respectively(p= 0.22). The intervention group complained of dyspnea for 2.4 days and the value for the controlwas 4.4 days (p=0.024). Values for ear pain were 0.5 and 1.6 days (p=0.008) respectively. The average numberof episodes of respiratory infection in the intervention group was 0.9 day, which was statistically fewer than thatin the control group (1.4 days), P=0.009.

CONCLUSIONS:A reduction in the number of episodes of respiratory infections and duration of some symptomssuch as dyspnea and ear pain was observed. Due to the reduction in upper respiratory tract infections of theathletes following intake of probiotic yogurt, improvement in VO2max is possible.

BACKGROUND/OBJECTIVE:The purpose of the present study was to evaluate the effect of fenugreek seed extract in combination with swimming exercise compared to glibenclamide consumption on type 2 diabetic rats.

DESIGN:The acute toxicity test was carried out to choose the safe doses and identify the toxicity effects of the fenugreek seed extract. To investigate the hypoglycemic effect of the extract and its effect in combination with swimming training, 80 Wistar Kyoto male streptozotocin-induced diabetic rats were divided randomly into eight groups: diabetic control (C); fenugreek seed extract 0.8 g/kg (F1); fenugreek extract 1.6 g/kg (F2); swimming training (S); swimming training plus fenugreek extract 0.8 g/kg (SF1); swimming training plus fenugreek extract 1.6 g/kg (SF2); glibenclamide (G) and swimming training plus glibenclamide (SG). The rats were orally administrated with the treatments once a day with the respective treatment, and the training groups were subjected to swimming training every day for 60 min. Fasting blood samples were collected to measure fasting blood glucose, lipid profile, adiponectin, leptin, and insulin concentrations.

RESULTS:The results obtained from acute toxicity study showed no toxicity effect of fenugreek seed extract on the tested dose. Biochemical analysis showed significant improvements in all of the groups compared to the control group (p<0.05). Plasma insulin concentration and insulin resistance (HOMA-IR) was significantly reduced in treated groups compared with the diabetic control group. Plasma leptin were significantly decreased in treated groups compared with the control group; while adiponectin had markedly increased (p<0.05).

CONCLUSION:The findings suggest that fenugreek seed consuming, alongside swimming exercise, has a strong therapeutic effect on the improvement of diabetic parameters.

BACKGROUND/OBJECTIVE:The purpose of the present study was to evaluate the effect of fenugreek seed extract in combination with swimming exercise compared to glibenclamide consumption on type 2 diabetic rats.

DESIGN:The acute toxicity test was carried out to choose the safe doses and identify the toxicity effects of the fenugreek seed extract. To investigate the hypoglycemic effect of the extract and its effect in combination with swimming training, 80 Wistar Kyoto male streptozotocin-induced diabetic rats were divided randomly into eight groups: diabetic control (C); fenugreek seed extract 0.8 g/kg (F1); fenugreek extract 1.6 g/kg (F2); swimming training (S); swimming training plus fenugreek extract 0.8 g/kg (SF1); swimming training plus fenugreek extract 1.6 g/kg (SF2); glibenclamide (G) and swimming training plus glibenclamide (SG). The rats were orally administrated with the treatments once a day with the respective treatment, and the training groups were subjected to swimming training every day for 60 min. Fasting blood samples were collected to measure fasting blood glucose, lipid profile, adiponectin, leptin, and insulin concentrations.

RESULTS:The results obtained from acute toxicity study showed no toxicity effect of fenugreek seed extract on the tested dose. Biochemical analysis showed significant improvements in all of the groups compared to the control group (p<0.05). Plasma insulin concentration and insulin resistance (HOMA-IR) was significantly reduced in treated groups compared with the diabetic control group. Plasma leptin were significantly decreased in treated groups compared with the control group; while adiponectin had markedly increased (p<0.05).

CONCLUSION:The findings suggest that fenugreek seed consuming, alongside swimming exercise, has a strong therapeutic effect on the improvement of diabetic parameters.

BACKGROUND:Urtica dioica (UD) has been identified as a traditional herbal medicine. This study aimed to investigate the effect of UD extract and swimming activity on diabetic parameters through in vivo and in vitro experiments.

METHODS:Adult WKY male rats were randomly distributed in nine groups: intact control, diabetic control, diabetic + 625 mg/kg, 1.25 g/kg UD, diabetic + 100 mg/kg Metformin, diabetic + swimming, diabetic + swimming 625 mg/kg, 1.25 g/kg UD, and diabetic +100 mg/kg Metformin + swimming. The hearts of the animals were punctured, and blood samples were collected for biochemical analysis. The entire pancreas was exposed for histologic examination. The effect of UD on insulin secretion by RIN-5F cells in 6.25 or 12.5 mM glucose dose was examined. Glucose uptake by cultured L6 myotubes was determined.

RESULTS:The serum glucose concentration decreased, the insulin resistance and insulin sensitivity significantly increased in treated groups. These changes were more pronounced in the group that received UD extract and swimming training. Regeneration and less beta cell damage of Langerhans islets were observed in the treated groups. UD treatment increased insulin secretion in the RIN-5F cells and glucose uptake in the L6 myotubes cells.

CONCLUSIONS:Swimming exercises accompanied by consuming UD aqueous extracts effectively improved diabetic parameters, repaired pancreatic tissues in streptozotocin-induced diabetics in vivo, and increased glucose uptake or insulin in UD-treated cells in vitro.

Low-intensity swimming training, started at an early age, was undertaken to observe glycemic control in hypothalamic obese mice produced by neonatal monosodium l-glutamate (MSG) treatment. Although swimming exercises by weaning pups inhibited hypothalamic obesity onset and recovered sympathoadrenal axis activity, this event was not observed when exercise training is applied to young adult mice. However, the mechanisms producing this improved metabolism are still not fully understood. Current work verifies whether, besides reducing fat tissue accumulation, low-intensity swimming in MSG-weaned mice also improves glycemic control. Although MSG and control mice swam for 15 min/day, 3 days a week, from the weaning stage up to 90 days old, sedentary MSG and normal mice did not exercise at all. After 14 h of fasting, animals were killed at 90 days of age. Retroperitonial fat accumulation was measured to estimate obesity. Fasting blood glucose and insulin concentrations were also measured. Mice were also submitted to ipGTT. MSG obese mice showed fasting hyperglycemia, hyperinsulinemia, and glucose intolerance and insulin resistance. However, the exercise was able to block MSG treatment effects. Higher total cholesterol and triglycerides observed in MSG mice were normalized by exercise after weaning. Exercised MSG animals had higher HDLc than the sedentary group. Data suggest that early exercise training maintains normoglycemia, insulin tissue sensitivity, and normal lipid profile in mice programmed to develop metabolic syndrome.

In previous studies, Nigella sativa (NS) has been studied due to its various physiological and pharmacological activities. However, evidence on the effects of NS on physical fatigue following exhaustive swimming remains limited. In the present study, the authors evaluated the potential beneficial effects of NS against the fatigue activity following exhaustive swimming. Rats were orally administered with NS extract (2 g/kg/day) for 21 days, and the anti-fatigue effect was assessed by exhaustive swimming exercise. The presented results indicated that pre-treatment of NS extract significantly increased the time to exhaustion. In hemodynamic parameters, NS extract increased blood pO2 and O2sat, but decreased pCO2. For underlying mechanisms, NS extract protected depletion of energy, indicated by increased levels of blood pH, glucose and tissue glycogen contents, and decreased levels of blood lactate, tissue lactic dehydrogenase and creatine kinase, when the NS extract was pre-treated. In addition, the NS extract inhibited oxidative stress following exhaustive swimming, as reflected by the results of increased levels of superoxide dismutase and redox ratio, and decreased the level of malondialdehyde when the NS extract was pre-treated. Collectively, the present study demonstrated that NS extract has an anti-fatigue activity against exhaustive swimming by energy restoration and oxidative-stress defense.

Nerve-induced muscle contraction regulates the BDNF/TrkB neurotrophic signalling to retrogradely modulate neurotransmission and protect the neuromuscular junctions and motoneurons. In muscles with amyotrophic lateral sclerosis, this pathway is strongly misbalanced and neuromuscular junctions are destabilized, which may directly cause the motoneuron degeneration and muscular atrophy observed in this disease. Here, we sought to demonstrate (1) that physical exercise, whose recommendation has been controversial in amyotrophic lateral sclerosis, would be a good option for its therapy, because it normalizes and improves the altered neurotrophin pathway and (2) a plausible molecular mechanism underlying its positive effect. SOD1-G93A mice were trained following either running or swimming-based protocols since the beginning of the symptomatic phase (day 70 of age) until day 115. Next, the full BDNF pathway, including receptors, downstream kinases and proteins related with neurotransmission, was characterized and motoneuron survival was analysed. The results establish that amyotrophic lateral sclerosis-induced damaging molecular changes in the BDNF/TrkB pathway are reduced, prevented or even overcompensated by precisely defined exercise protocols that modulate TrkB isoforms and neurotransmission regulatory proteins and reduce motoneuron death. Altogether, the maintenance of the BDNF/TrkB signalling and the downstream pathway, particularly after the swimming protocol, adds new molecular evidence of the benefits of physical exercise to reduce the impact of amyotrophic lateral sclerosis. These results are encouraging since they reveal an improvement even starting the therapy after the onset of the disease.

Alzheimer's disease (AD) is associated with cognitive deficits and behavioral disorders such as anxiety and depression. Recent clinical and experimental studies have demonstrated that swimming exercise could be a potential therapy for cognitive and behavioral disorders. The prevalence of anxiety and depression is increasing among patients with AD; hence, further studies are needed to develop therapies for these behavioral abnormalities. The purpose of this study was to evaluate the effects of swimming exercise on memory impairment, anxiety, and depression-like behaviors in a mouse model of sporadic Alzheimer-like disease. Eight days after AD induction by streptozotocin (STZ), mice were subjected to the swimming exercise for four weeks. To assess cognitive functions, anxiety- and depression-related behaviors in animals, Y-maze, novel object recognition, open field, zero maze, sucrose preference, and forced swim tests were used. To understand the possible mechanisms, amyloid-β (Aβ)-42, brain-derived neurotrophic factor (BDNF), glutamate, malondialdehyde (MDA), tumor-necrosis-factor (TNF)-α, and interleukin (IL)-6 levels were measured in the hippocampus. The results of this study indicate that STZ administration impaired cognitive functions, increased anxiety- and depression-related behaviors, and elevated Aβ-42, glutamate, MDA, TNF-α, and IL-6 levels in the hippocampus of mice. In contrast, swimming exercise significantly reversed these neurobehavioral disorders, increased BDNF, and decreased both glutamate and TNF-α in the hippocampus of STZ-treated mice. Overall, these findings provide some support for the idea that swimming exercise might be associated with reduced neurobehavioral disorders in patients with Alzheimer's disease. However, further clinical studies on this topic are required to confirm and validate these findings.

High-intensity interval training has drawn significant interest for its ability to elicit similar training responses with less training volume compared to traditional moderate-intensity protocols. The purpose of this study was to examine the effect of co-ingestion of branched-chain amino acids (BCAA), arginine, and citrulline on 8× 50 m high-intensity interval swim performance in trained young swimmers. This study used a randomized cross-over design. Eight male (age 15.6 ± 1.3 years) and eight female (age 15.6 ± 0.9 years) swimmers completed both amino acids (AA) and placebo (PL) trials. The participants ingested 0.085 g/kg body weight BCAA, 0.05 g/kg body weight arginine and 0.05 g/kg body weight citrulline before the swim test in the AA trial. The average 50 m time was significantly shorter in the AA trial than that in the PL trial. The AA trial was faster than the PL trial in the first, second, and the seventh laps. The AA trial showed significantly higher plasma BCAA concentrations and lower tryptophan/BCAA ratio. The other biochemical parameters and ratings of perceived exertion were similar between the two trials. The results showed that BCAA, arginine, and citrulline, allowed the participants to swim faster in a high-intensity interval protocol in young swimmers.

BACKGROUND:Resistive breathing practices are known to improve endurance and performance in competitive swimmers. However, the effect of Pranayama or Yogic Breathing Practices (YBP) in improving respiratory endurance and performance of competitive swimmers remains un-investigated.

OBJECTIVES:To study effects of yogic breathing practices on lung functions of swimmers.

MATERIAL AND METHODS:Twenty seven national and international competitive swimmers of the age range 13-20 years, with 8.29 ± 2.9 years of competitive swimming experience and practicing swimming for 9.58 ± 1.81 km everyday, were assigned randomly to either an experimental (YBP) or to wait list control group (no intervention). Outcome measures were taken on day 1 and day 30 and included (1) spirometry to measure lung function, (2) Sport Anxiety Scale-2 (SAS-2) to measure the antecedents and consequences of cognitive and somatic trait anxiety of sport performance and (3) number of strokes per breath to measure performance. The YBP group practiced a prescribed set of Yogic Breathing Practices - Sectional Breathing (Vibhagiya Pranayama), Yogic Bellows Breathing (Bhastrika Pranayama) and Alternate Nostril Breathing with Voluntary Internal Breath Holding (Nadi Shodhana with Anthar kumbhaka) for half an hour, five days a week for one month.

RESULTS:There was a significant improvement in the YBP group as compared to control group in maximal voluntary ventilation (p = 0.038), forced vital capacity (p = 0.026) and number of strokes per breath (p = 0.001).

CONCLUSION:The findings suggest that YBP helps to enhance respiratory endurance in competitive swimmers.