[Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no...[Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no swimming,administered intragastrically the same volume of distilled water; simple swimming group: free swimming,administered intragastrically the same volume of distilled water; maca extract groups: free swimming,and treated with 4. 0,5. 3,and 8. 0 g/kg dose of maca extracts. Swimming rats swam freely in the circulating water flow of swimming pool and administered for 15 d. On the 16 th d,after the swimming endurance test,the rats were killed painlessly. The ultrastructure of the mitochondria in the spinal neurons was observed with a projection electron microscope,muscle glycogen,malondialdehyde( MDA),superoxide dismutase( SOD),glutathione peroxidase( GSH-Px) and free calcium in muscle were measured by radioimmunoassay.[Results] Compared with the simple swimming group,the swimming time before sinking and total swimming time extended 19. 83%,60. 28%,77. 55% and 55. 34%,73. 91% and 94. 47% respectively,and the differences were statistically significant( P < 0. 01). The sinking times decreased by 34. 35%,51. 18% and 57. 96% respectively,the differences were statistically significant( P < 0. 01). MDA and free calcium decreased by 20. 10%,31. 49% and 38. 72%,respectively with statistically significant differences( P < 0. 01) and 6. 42%,17. 58%and 26. 35% respectively. The levels of SOD,GSH-Px and muscle glycogen increased by 5. 12%,22. 74%,52. 53%,44. 22%,77. 79%and 98. 45% respectively,with statistically significant differences( P < 0. 01) and 35. 08%,47. 83% and 81. 88%,respectively,with statistically significant differences( P < 0. 01). The volume density( Vd),surface density( Sd) and number density( Nd) of mitochondria of spinal neurons decreased by 7. 79%,18. 18%,31. 17%,16. 95%,27. 34%,43. 31% and 13. 51%,23. 19% and 43. 15% respectively.[Conclusions]Maca extract can protect ultrastructure of the mitochondria in the spinal neurons,antioxidant activity,increase muscle glycogen,and improving the exercise capacity.展开更多
Background Stable angina pectoris is a common subtype of coronary heart disease.Patients suffer from chest tightness,chest pain and crushing pain under the inducement of fatigue and emotional agitation.This study aims...Background Stable angina pectoris is a common subtype of coronary heart disease.Patients suffer from chest tightness,chest pain and crushing pain under the inducement of fatigue and emotional agitation.This study aims to investigate the effect of exercise training guidance based on action research on exercise endurance and readmission rate of patients with stable angina pectoris.Methods A retrospective study was conducted on 60 patients with stable angina pectoris due to coronary heart disease admitted to our hospital from February 2020 to November 2023.Patients were divided into a control group of 29 cases(receiving conventional exercise training guidance)and a guidance group of 31 cases(receiving action research-based exercise training guidance).Both groups received continuous training for one month.A comparison was made between the exercise endurance indicators[6-minute walk test distance(6MWT),peak oxygen consumption(peak VO2),anaerobic threshold(AT),exercise duration(ED)],quality of life,and readmission rate within 6 months after intervention in both groups.Results After 1 month of intervention,6MWT,peak VO2,AT and ED were increased in both groups,and those in the guidance group were higher than those in the conventional group(P<0.05).The score of quality of life(The 36-item shot-form health status survey,SF-36)in both groups was increased,and the guidance group scored higher than the conventional group(P<0.05).The readmission rate of patients in the guidance group was 6.45%,which was lower than that in the conventional group(27.59%)(P<0.05).Conclusions The application of action research-based exercise training guidance in patients with stable angina pectoris due to coronary heart disease has significant effects,improving exercise endurance,significantly improving quality of life,and reducing readmission rate,thus having practical value.[S Chin J Cardiol 2024;25(3):162-168]展开更多
Objective:To explore the effect of N-acetylcysteine combined with lung rehabilitation therapy on exercise endurance and quality of life in patients with rheumatoid arthritis-related interstitial lung disease(RA-ILD).M...Objective:To explore the effect of N-acetylcysteine combined with lung rehabilitation therapy on exercise endurance and quality of life in patients with rheumatoid arthritis-related interstitial lung disease(RA-ILD).Methods:Fifty-six patients with RA-ILD admitted to Xijing Hospital from May 2022 to January 2024 were randomly divided into two groups:a non-rehabilitation group and a pulmonary rehabilitation group,with 28 patients in each group.Both groups received routine treatment.Additionally,the non-rehabilitation group received N-acetylcysteine treatment,while the lung rehabilitation group received lung rehabilitation treatment in addition to N-acetylcysteine.The improvement in exercise endurance and dyspnea between the two groups after treatment was compared and the quality of life of the patients was observed.Results:After treatment,the exercise endurance score in the lung rehabilitation group(335.67±45.29)was higher than that in the non-rehabilitation group(P<0.05).The dyspnea score in the lung rehabilitation group(0.72±0.16)was lower than that in the non-rehabilitation group(P<0.05).Additionally,FVC(3.18±0.58 L),FEV1(2.28±0.56 L),FEV1/FVC(69.69±5.56),and DLCO(60.53±5.92 mL/mmHg/min)were higher in the lung rehabilitation group compared to the non-rehabilitation group after treatment(P<0.05).Conclusion:Lung rehabilitation therapy combined with N-acetylcysteine treatment can effectively improve dyspnea symptoms,lung function,and exercise endurance in patients with RA-ILD.This approach helps to improve patient’s quality of life and is beneficial for their prognosis.展开更多
After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neuro...After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neurotoxicity were measured by enzyme-linked immunosorbent assay method. 8 weeks of treadmill exercise significantly increased brain-derived neurotrophic factor level in the hippocampus （P = 0.04） and plasma level of total antioxidant capacity of rats exposed to lead acetate （P 〈 0.001）, and significantly decreased plasma level of malondialdehyde （P 〈 0.001）. Acute exercise only decreased the hippocampal malondialdehyde level （P = 0.09） and increased brain-derived neurotrophic factor level in the hippocampus （P = 0.66）. Acute exercise also enhanced the total antioxidant capacity in rats exposed to lead acetate, insignificantly （P = 0.99）, These findings suggest that chronic treadmill exercise can significantly decrease neurotoxicity and alleviate oxidative stress in rats exposed to lead acetate. However, acute endurance exercise was not associated with these beneficial effects.展开更多
Background:Smokeless tobacco is widely used by athletes to enhance performance.Nicotine is a central nervous system stimulant and acts on cardiocirculatory and metabolic systems,involving tissue blood flow and circula...Background:Smokeless tobacco is widely used by athletes to enhance performance.Nicotine is a central nervous system stimulant and acts on cardiocirculatory and metabolic systems,involving tissue blood flow and circulatory vasoreactivity.The aim of this study was to investigate the effects of the oral smokeless tobacco(Swedish snus(SS))on the perception of fatigue and time to exhaustion(TTE)during moderate-intensity aerobic exercise.Methods:Fourteen healthy non-tobacco male users were recruited for a double-blind,controlled crossover design(SS vs.snus placebo(SP)).Subjects were tested for 3 sessions:experimental session 1(Exp 1)consisted of an incremental test to determine the maximal aerobic power out-put(Wmax),whereas Exp2 and Exp3 consisted of exercising at 65%Wmax until exhaustion in SS or SP conditions.During Exp2 and Exp3,muscle and cerebral oxygenation was assessed by means of near-infrared spectroscopy,and the rating of perceived exertion(RPE)was recorded.Results:Comparing SS with SP tests,significant differences(p〈0.05)were found in the values of cerebral(-3%)and muscular tissues oxygenation(-4%)in the first 30 min of exercise.The RPE values were not significantly different between the 2 conditions(SS vs.SP).No significant difference was found in TTE(SS:54.25±21.84 min;SP:50.01±17.03 min).Conclusion:This study showed that muscular and cerebral oxygenation increased significantly with snus administration during an endurance exercise until exhaustion,but this did not affect fatigue perception and TTE.The results showed that snus could not be considered an ergogenic substance in non-tobacco users.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.(http://creativecommons.org/licenses/by-nc-nd/4.0/).展开更多
AIM: To investigate whether American ginseng (AG, Panax quinquefolium) supplementation was able to improve endurance exercise performance.METHODS: Thirteen physically active male college students were divided into two...AIM: To investigate whether American ginseng (AG, Panax quinquefolium) supplementation was able to improve endurance exercise performance.METHODS: Thirteen physically active male college students were divided into two groups (AG or placebo)and received supplementation for 4 wk, before the exhaustive running exercise. Treadmill speed was increased to a pace equivalent to 80% VO2max of the subject. A 4-wk washout period followed before the subjects crossed over and received the alternate supplement for the next 4 wk.They then completed a second exhaustive running exercise. The physiological variables that were examined included time to exhaustion and oxygen pulse. Moreover,the plasma creatine kinase (CK) and lactate were measured prior to the exercise, at 15 and 30 min during exercise,immediately after exercise, and 20, 40, 60, and 120 min after exercise.RESULTS: The major finding of this investigation was that the production plasma CK during the exercise significantly decreased for group AG than for group P. Secondary physiological finding was that 80% VO2max running was not improved over a 4-wk AG supplementation regimen.CONCLUSION: Supplementation with AG for 4 wk prior to an exhaustive aerobic treadmill running reduced the leakage of CK during exercise, but did not enhance aerobic work capacity. The reduction of plasma CK may be due to the fact that AG is effective for the decrease of skeletal muscle cell membrane damage, induced by exercise during the high-intensity treadmill run.展开更多
Background:Pacing,defined as percentage changes of speed between successive splits,has been extensively studied in running and cycling endurance sports;however,less information about the trends in change of speed duri...Background:Pacing,defined as percentage changes of speed between successive splits,has been extensively studied in running and cycling endurance sports;however,less information about the trends in change of speed during cross-country(XC)ski racing is available.Therefore,the aim of the present study was to examine the effect of performance(quartiles of race time(Q),with Q1 the fastest and Q4 the slowest)level on pacing in the Vasaloppet ski race,the largest XC skiing race in the world.Methods:For this purpose,we analyzed female(n=19,465)and male(n=164,454)finishers in the Vasaloppet ski race from 2004 to 2017 using a one-way(2 sexes)analysis of variance with repeated measures to examine percentage changes of speed between 2 successive splits.Overall,the race consisted of 8 splits.Results:The race speeds of Q1,Q2,Q3,and Q4 were 13.6±1.8,10.6±0.5,9.2±0.3,and 8.1±-0.4 km/h,respectively,among females and 16.7±1.7,13.1±0.7,10.9±0.6,and 8.9±0.7 km/h,respectively,among males.The overall pacing strategy of finishers was variable.A small sex×split interaction on speed was observed(η^2=0.016,p〈0.001),with speed difference between sexes ranging from 14.9%(Split 7)to 27.0%(Split 1)and larger changes in speed between 2 successive splits being shown for females(p〈0.001,η^2=0.004).A large performance×split interaction on speed,with Q1 presenting the smallest changes of speed between splits,was shown for females(η^2=0.149,p〈0.001)and males(η^2=0.169,p〈0.001).Conclusion:Male and fast XC skiers are more even pacers.Coaches and athletes should develop tailored sex-and performance-level pacing strategies;for instance,they should advise fast XC skiers to start fast and maintain their speed,rather than starting slowly and trying to make up time by going faster at times during the race.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.展开更多
Objective: This study aimed to evaluate the influence of oral supplementation with benfotiamine on oxidative stress in the liver, heart and muscles of endurance-trained mice.Methods: Twenty-five male BALB/c mice were ...Objective: This study aimed to evaluate the influence of oral supplementation with benfotiamine on oxidative stress in the liver, heart and muscles of endurance-trained mice.Methods: Twenty-five male BALB/c mice were allocated to the following treatment groups: standard diet and sedentary activity(Sta–Sed), benfotiamine–supplemented diet and sedentary activity(Ben–Sed),standard diet and training activity(Sta–Tr) and benfotiamine–supplemented diet and training activity(Ben–Tr). The training comprised 6 weeks of endurance swimming training. The concentration of thiobarbituric acid reactive substances(TBARS), carbonylated proteins, total thiols and non-protein thiols was analyzed in the liver, heart and tibialis anterior muscle.Results: In the muscle, TBARS concentration in the Sta–Sed group was higher than that in other groups;in the heart, TBARS concentration in the Sta–Sed and Ben–Tr groups was higher than that in the Ben–Sed group. The carbonyl content of the muscle tissues was higher in the Sta–Sed group than in both supplemented groups. In liver, the carbonyl content was lower in the Ben–Sed group than in the Sta–Sed group.The level of total thiols was lower in the Ben–Sed group than in the Sta–Tr group. In the heart, the level of total thiols was higher in the Ben–Sed group than in the Ben–Tr group. The concentration of non-protein thiols in the muscle was higher in the Ben–Sed group than in the Ben–Tr group, whereas in the heart, concentration of non-protein thiols of Sta–Tr group was lower than that of Sta–Sed group.Conclusion: The results show that benfotiamine is an efficient antioxidant for the anterior tibialis muscle and heart;however, swimming training did not alter redox status.展开更多
Objective: Progesterone (P4) is the optimal agent for luteal support in assisted reproductive technologies. Despite the availability of various formulations, the impacts of P4 treatment administered through different ...Objective: Progesterone (P4) is the optimal agent for luteal support in assisted reproductive technologies. Despite the availability of various formulations, the impacts of P4 treatment administered through different routes on offspring growth remain unevaluated. This study aimed to investigate and compare the effects of P4 administration through three different routes in pregnant rats during the teratogenesis-sensitive period on fertility outcomes and the behavior, plasma P4 and pregnenolone levels, and alterations in gut microbiota in the filial generation (F1) of offspring.Methods: Female rats that mated successfully were randomly classified into four groups: Group 1, the normal control group;Group 2, the IG group, in which utrogestan was administeredvia intragastric gavage;Group 3, the IM group, in which P4 was administeredvia intramuscular injection;and Group 4, the VAGIN group, in which P4 sustained-release vaginal gel was administered through the vagina. Except for the control group, P4 was administered in other groups through their respective routes for 13 consecutive days daily during the teratogenic-sensitive gestation period (days 6–18). The fertility outcomes of the maternal rats were observed, and open-field and three-chamber social preference tests were conducted to assess anxiety and social behavior, along with an exhaustive swimming experiment to evaluate the motor endurance of the offspring. Plasma P4 and pregnenolone levels in the offspring were measured, and fecal samples were assessed using gut microbiota sequencing and subsequent bioinformatics analysis.Results: No significant alterations in fertility outcomes were observed through three P4 administration routes-intragastric gavage, intramuscular injection, and vaginal administration-in rats. However, in behavioral experiments in offspring, a significant increase was observed in swimming time in the IG group than in the control group (P = 0.013). Furthermore, the offspring in the IG group exhibited a marked decrease in non-social behaviors compared with the control group (P = 0.030). No significant behavioral changes were observed in the F1 offspring in the open-field test. Additionally, the offspring in the IG group exhibited a significant elevation in plasma pregnenolone levels compared with the control group (P = 0.019) 30 days after birth. No notable differences in the α-diversity of gut microbiota were observed among the groups. However, significant differences in β-diversity were observed in both the IG and IM groups compared with the control group, indicating that P4 treatmentvia the two routes exhibited a significant impact on the gut microbiota composition of F1 offspring. Distinct differences were observed in the gut microbiota of the offspring among the three P4 treatment groups, with 22, 28, and 33 differential bacterial taxa identified in the IG, IM, and VAGIN groups, respectively, using linear discriminant effect size analysis, whereasOlivella appeared exclusively in the control group rather than in the P4 treatment groups.Conclusion: Oral administration of P4 to maternal rats during the teratogenesis-sensitive period enhanced motor endurance and plasma pregnenolone levels and altered the composition of the gut microbiota in the offspring. Our findings demonstrated different effects on offspring growth when P4 is administered orally, intramuscularly, or vaginally.展开更多
Background:Habitual physical activity is known to support cardiovascular health.However,when intensive exercise is performed for long durations,it can negatively affect the cardiovascular system.We evaluated the exerc...Background:Habitual physical activity is known to support cardiovascular health.However,when intensive exercise is performed for long durations,it can negatively affect the cardiovascular system.We evaluated the exercise-induced physiological responses of cardiac markers in male marathon runners based on basal plasma trimethylamine-N-oxide(TMAO)levels,a metabolite related to major adverse cardiovascular events.Methods:Blood samples from 28 marathon runners were collected two weeks before the marathon run(baseline),after finishing the race(post-marathon),and two weeks after the race(2 weeks post-marathon).Serum cardiac troponin I(c Tn I),endothelin-1(ET-1),galectin-3,pentraxin-3,human growth differentiation factor 15,and neopterin were determined by the enzyme immunoassay method.Plasma trimethylamine(TMA)and TMAO were measured by the ultra-high-performance liquid chromatography-mass spectrometry method.Results:Running a marathon increased levels of circulating biomarkers.A greater post-marathon elevation of cTn I and ET-1 was associated with baseline plasma TMAO levels(R=0.400,p=0.035 and R=0.476,p=0.012,respectively).Moreover,we observed an increase in post-marathon TMA levels.Conclusion:Greater post-marathon elevation of cTn I and ET-1 was associated with higher baseline plasma TMAO levels.Therefore,TMAO could potentially serve as a new marker in assessing the response of cardiovascular stress biomarkers to marathon running.展开更多
基金Supported by Science and Technology Planning Project of Lanzhou City(2015-3-80)Science and Technology Innovation Team Project for Universities in Gansu Province(2016C-09)+3 种基金Talent Innovation and Entrepreneurship Project of Lanzhou City(2016-RC-85)Gansu Natural Science Foundation Project(17JR5RA158)Investigation Theory and Practice Research Center Project of Northwest Minority AreasGansu Province Evidence Science Characteristic Discipline Project
文摘[Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no swimming,administered intragastrically the same volume of distilled water; simple swimming group: free swimming,administered intragastrically the same volume of distilled water; maca extract groups: free swimming,and treated with 4. 0,5. 3,and 8. 0 g/kg dose of maca extracts. Swimming rats swam freely in the circulating water flow of swimming pool and administered for 15 d. On the 16 th d,after the swimming endurance test,the rats were killed painlessly. The ultrastructure of the mitochondria in the spinal neurons was observed with a projection electron microscope,muscle glycogen,malondialdehyde( MDA),superoxide dismutase( SOD),glutathione peroxidase( GSH-Px) and free calcium in muscle were measured by radioimmunoassay.[Results] Compared with the simple swimming group,the swimming time before sinking and total swimming time extended 19. 83%,60. 28%,77. 55% and 55. 34%,73. 91% and 94. 47% respectively,and the differences were statistically significant( P < 0. 01). The sinking times decreased by 34. 35%,51. 18% and 57. 96% respectively,the differences were statistically significant( P < 0. 01). MDA and free calcium decreased by 20. 10%,31. 49% and 38. 72%,respectively with statistically significant differences( P < 0. 01) and 6. 42%,17. 58%and 26. 35% respectively. The levels of SOD,GSH-Px and muscle glycogen increased by 5. 12%,22. 74%,52. 53%,44. 22%,77. 79%and 98. 45% respectively,with statistically significant differences( P < 0. 01) and 35. 08%,47. 83% and 81. 88%,respectively,with statistically significant differences( P < 0. 01). The volume density( Vd),surface density( Sd) and number density( Nd) of mitochondria of spinal neurons decreased by 7. 79%,18. 18%,31. 17%,16. 95%,27. 34%,43. 31% and 13. 51%,23. 19% and 43. 15% respectively.[Conclusions]Maca extract can protect ultrastructure of the mitochondria in the spinal neurons,antioxidant activity,increase muscle glycogen,and improving the exercise capacity.
文摘Background Stable angina pectoris is a common subtype of coronary heart disease.Patients suffer from chest tightness,chest pain and crushing pain under the inducement of fatigue and emotional agitation.This study aims to investigate the effect of exercise training guidance based on action research on exercise endurance and readmission rate of patients with stable angina pectoris.Methods A retrospective study was conducted on 60 patients with stable angina pectoris due to coronary heart disease admitted to our hospital from February 2020 to November 2023.Patients were divided into a control group of 29 cases(receiving conventional exercise training guidance)and a guidance group of 31 cases(receiving action research-based exercise training guidance).Both groups received continuous training for one month.A comparison was made between the exercise endurance indicators[6-minute walk test distance(6MWT),peak oxygen consumption(peak VO2),anaerobic threshold(AT),exercise duration(ED)],quality of life,and readmission rate within 6 months after intervention in both groups.Results After 1 month of intervention,6MWT,peak VO2,AT and ED were increased in both groups,and those in the guidance group were higher than those in the conventional group(P<0.05).The score of quality of life(The 36-item shot-form health status survey,SF-36)in both groups was increased,and the guidance group scored higher than the conventional group(P<0.05).The readmission rate of patients in the guidance group was 6.45%,which was lower than that in the conventional group(27.59%)(P<0.05).Conclusions The application of action research-based exercise training guidance in patients with stable angina pectoris due to coronary heart disease has significant effects,improving exercise endurance,significantly improving quality of life,and reducing readmission rate,thus having practical value.[S Chin J Cardiol 2024;25(3):162-168]
文摘Objective:To explore the effect of N-acetylcysteine combined with lung rehabilitation therapy on exercise endurance and quality of life in patients with rheumatoid arthritis-related interstitial lung disease(RA-ILD).Methods:Fifty-six patients with RA-ILD admitted to Xijing Hospital from May 2022 to January 2024 were randomly divided into two groups:a non-rehabilitation group and a pulmonary rehabilitation group,with 28 patients in each group.Both groups received routine treatment.Additionally,the non-rehabilitation group received N-acetylcysteine treatment,while the lung rehabilitation group received lung rehabilitation treatment in addition to N-acetylcysteine.The improvement in exercise endurance and dyspnea between the two groups after treatment was compared and the quality of life of the patients was observed.Results:After treatment,the exercise endurance score in the lung rehabilitation group(335.67±45.29)was higher than that in the non-rehabilitation group(P<0.05).The dyspnea score in the lung rehabilitation group(0.72±0.16)was lower than that in the non-rehabilitation group(P<0.05).Additionally,FVC(3.18±0.58 L),FEV1(2.28±0.56 L),FEV1/FVC(69.69±5.56),and DLCO(60.53±5.92 mL/mmHg/min)were higher in the lung rehabilitation group compared to the non-rehabilitation group after treatment(P<0.05).Conclusion:Lung rehabilitation therapy combined with N-acetylcysteine treatment can effectively improve dyspnea symptoms,lung function,and exercise endurance in patients with RA-ILD.This approach helps to improve patient’s quality of life and is beneficial for their prognosis.
文摘After intraperitoneal injection of 20 mg/kg lead acetate, rats received 8 weeks of treadmill exercise （15-22 m/min, 25-64 minutes） and/or treadmill exercise at 1.6 km/h until exhaustion. The markers related to neurotoxicity were measured by enzyme-linked immunosorbent assay method. 8 weeks of treadmill exercise significantly increased brain-derived neurotrophic factor level in the hippocampus （P = 0.04） and plasma level of total antioxidant capacity of rats exposed to lead acetate （P 〈 0.001）, and significantly decreased plasma level of malondialdehyde （P 〈 0.001）. Acute exercise only decreased the hippocampal malondialdehyde level （P = 0.09） and increased brain-derived neurotrophic factor level in the hippocampus （P = 0.66）. Acute exercise also enhanced the total antioxidant capacity in rats exposed to lead acetate, insignificantly （P = 0.99）, These findings suggest that chronic treadmill exercise can significantly decrease neurotoxicity and alleviate oxidative stress in rats exposed to lead acetate. However, acute endurance exercise was not associated with these beneficial effects.
基金supported by research funds allocated to the following departments at the University of Verona:Neurosciences,Biomedicine and Movement Sciences,and Diagnostic and Public Health
文摘Background:Smokeless tobacco is widely used by athletes to enhance performance.Nicotine is a central nervous system stimulant and acts on cardiocirculatory and metabolic systems,involving tissue blood flow and circulatory vasoreactivity.The aim of this study was to investigate the effects of the oral smokeless tobacco(Swedish snus(SS))on the perception of fatigue and time to exhaustion(TTE)during moderate-intensity aerobic exercise.Methods:Fourteen healthy non-tobacco male users were recruited for a double-blind,controlled crossover design(SS vs.snus placebo(SP)).Subjects were tested for 3 sessions:experimental session 1(Exp 1)consisted of an incremental test to determine the maximal aerobic power out-put(Wmax),whereas Exp2 and Exp3 consisted of exercising at 65%Wmax until exhaustion in SS or SP conditions.During Exp2 and Exp3,muscle and cerebral oxygenation was assessed by means of near-infrared spectroscopy,and the rating of perceived exertion(RPE)was recorded.Results:Comparing SS with SP tests,significant differences(p〈0.05)were found in the values of cerebral(-3%)and muscular tissues oxygenation(-4%)in the first 30 min of exercise.The RPE values were not significantly different between the 2 conditions(SS vs.SP).No significant difference was found in TTE(SS:54.25±21.84 min;SP:50.01±17.03 min).Conclusion:This study showed that muscular and cerebral oxygenation increased significantly with snus administration during an endurance exercise until exhaustion,but this did not affect fatigue perception and TTE.The results showed that snus could not be considered an ergogenic substance in non-tobacco users.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.(http://creativecommons.org/licenses/by-nc-nd/4.0/).
基金Supported by the Taiwan Biotech Co., Taiwan, China
文摘AIM: To investigate whether American ginseng (AG, Panax quinquefolium) supplementation was able to improve endurance exercise performance.METHODS: Thirteen physically active male college students were divided into two groups (AG or placebo)and received supplementation for 4 wk, before the exhaustive running exercise. Treadmill speed was increased to a pace equivalent to 80% VO2max of the subject. A 4-wk washout period followed before the subjects crossed over and received the alternate supplement for the next 4 wk.They then completed a second exhaustive running exercise. The physiological variables that were examined included time to exhaustion and oxygen pulse. Moreover,the plasma creatine kinase (CK) and lactate were measured prior to the exercise, at 15 and 30 min during exercise,immediately after exercise, and 20, 40, 60, and 120 min after exercise.RESULTS: The major finding of this investigation was that the production plasma CK during the exercise significantly decreased for group AG than for group P. Secondary physiological finding was that 80% VO2max running was not improved over a 4-wk AG supplementation regimen.CONCLUSION: Supplementation with AG for 4 wk prior to an exhaustive aerobic treadmill running reduced the leakage of CK during exercise, but did not enhance aerobic work capacity. The reduction of plasma CK may be due to the fact that AG is effective for the decrease of skeletal muscle cell membrane damage, induced by exercise during the high-intensity treadmill run.
文摘Background:Pacing,defined as percentage changes of speed between successive splits,has been extensively studied in running and cycling endurance sports;however,less information about the trends in change of speed during cross-country(XC)ski racing is available.Therefore,the aim of the present study was to examine the effect of performance(quartiles of race time(Q),with Q1 the fastest and Q4 the slowest)level on pacing in the Vasaloppet ski race,the largest XC skiing race in the world.Methods:For this purpose,we analyzed female(n=19,465)and male(n=164,454)finishers in the Vasaloppet ski race from 2004 to 2017 using a one-way(2 sexes)analysis of variance with repeated measures to examine percentage changes of speed between 2 successive splits.Overall,the race consisted of 8 splits.Results:The race speeds of Q1,Q2,Q3,and Q4 were 13.6±1.8,10.6±0.5,9.2±0.3,and 8.1±-0.4 km/h,respectively,among females and 16.7±1.7,13.1±0.7,10.9±0.6,and 8.9±0.7 km/h,respectively,among males.The overall pacing strategy of finishers was variable.A small sex×split interaction on speed was observed(η^2=0.016,p〈0.001),with speed difference between sexes ranging from 14.9%(Split 7)to 27.0%(Split 1)and larger changes in speed between 2 successive splits being shown for females(p〈0.001,η^2=0.004).A large performance×split interaction on speed,with Q1 presenting the smallest changes of speed between splits,was shown for females(η^2=0.149,p〈0.001)and males(η^2=0.169,p〈0.001).Conclusion:Male and fast XC skiers are more even pacers.Coaches and athletes should develop tailored sex-and performance-level pacing strategies;for instance,they should advise fast XC skiers to start fast and maintain their speed,rather than starting slowly and trying to make up time by going faster at times during the race.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport.This is an open access article under the CC BY-NC-ND license.
基金supported by Fundacao de Amparo a pesquisa de Minas Gerais(FAPEMIG)[grant number:APQ-00039-15]Conselho Nacional de Desenvolvimento Científico e Tecnologico(CNPq)[grant number:423171/2016-0]
文摘Objective: This study aimed to evaluate the influence of oral supplementation with benfotiamine on oxidative stress in the liver, heart and muscles of endurance-trained mice.Methods: Twenty-five male BALB/c mice were allocated to the following treatment groups: standard diet and sedentary activity(Sta–Sed), benfotiamine–supplemented diet and sedentary activity(Ben–Sed),standard diet and training activity(Sta–Tr) and benfotiamine–supplemented diet and training activity(Ben–Tr). The training comprised 6 weeks of endurance swimming training. The concentration of thiobarbituric acid reactive substances(TBARS), carbonylated proteins, total thiols and non-protein thiols was analyzed in the liver, heart and tibialis anterior muscle.Results: In the muscle, TBARS concentration in the Sta–Sed group was higher than that in other groups;in the heart, TBARS concentration in the Sta–Sed and Ben–Tr groups was higher than that in the Ben–Sed group. The carbonyl content of the muscle tissues was higher in the Sta–Sed group than in both supplemented groups. In liver, the carbonyl content was lower in the Ben–Sed group than in the Sta–Sed group.The level of total thiols was lower in the Ben–Sed group than in the Sta–Tr group. In the heart, the level of total thiols was higher in the Ben–Sed group than in the Ben–Tr group. The concentration of non-protein thiols in the muscle was higher in the Ben–Sed group than in the Ben–Tr group, whereas in the heart, concentration of non-protein thiols of Sta–Tr group was lower than that of Sta–Sed group.Conclusion: The results show that benfotiamine is an efficient antioxidant for the anterior tibialis muscle and heart;however, swimming training did not alter redox status.
文摘Objective: Progesterone (P4) is the optimal agent for luteal support in assisted reproductive technologies. Despite the availability of various formulations, the impacts of P4 treatment administered through different routes on offspring growth remain unevaluated. This study aimed to investigate and compare the effects of P4 administration through three different routes in pregnant rats during the teratogenesis-sensitive period on fertility outcomes and the behavior, plasma P4 and pregnenolone levels, and alterations in gut microbiota in the filial generation (F1) of offspring.Methods: Female rats that mated successfully were randomly classified into four groups: Group 1, the normal control group;Group 2, the IG group, in which utrogestan was administeredvia intragastric gavage;Group 3, the IM group, in which P4 was administeredvia intramuscular injection;and Group 4, the VAGIN group, in which P4 sustained-release vaginal gel was administered through the vagina. Except for the control group, P4 was administered in other groups through their respective routes for 13 consecutive days daily during the teratogenic-sensitive gestation period (days 6–18). The fertility outcomes of the maternal rats were observed, and open-field and three-chamber social preference tests were conducted to assess anxiety and social behavior, along with an exhaustive swimming experiment to evaluate the motor endurance of the offspring. Plasma P4 and pregnenolone levels in the offspring were measured, and fecal samples were assessed using gut microbiota sequencing and subsequent bioinformatics analysis.Results: No significant alterations in fertility outcomes were observed through three P4 administration routes-intragastric gavage, intramuscular injection, and vaginal administration-in rats. However, in behavioral experiments in offspring, a significant increase was observed in swimming time in the IG group than in the control group (P = 0.013). Furthermore, the offspring in the IG group exhibited a marked decrease in non-social behaviors compared with the control group (P = 0.030). No significant behavioral changes were observed in the F1 offspring in the open-field test. Additionally, the offspring in the IG group exhibited a significant elevation in plasma pregnenolone levels compared with the control group (P = 0.019) 30 days after birth. No notable differences in the α-diversity of gut microbiota were observed among the groups. However, significant differences in β-diversity were observed in both the IG and IM groups compared with the control group, indicating that P4 treatmentvia the two routes exhibited a significant impact on the gut microbiota composition of F1 offspring. Distinct differences were observed in the gut microbiota of the offspring among the three P4 treatment groups, with 22, 28, and 33 differential bacterial taxa identified in the IG, IM, and VAGIN groups, respectively, using linear discriminant effect size analysis, whereasOlivella appeared exclusively in the control group rather than in the P4 treatment groups.Conclusion: Oral administration of P4 to maternal rats during the teratogenesis-sensitive period enhanced motor endurance and plasma pregnenolone levels and altered the composition of the gut microbiota in the offspring. Our findings demonstrated different effects on offspring growth when P4 is administered orally, intramuscularly, or vaginally.
基金supported by the Polish Ministry of Science and Higher Education,grant no.2/566516/SPUB/SP/2023。
文摘Background:Habitual physical activity is known to support cardiovascular health.However,when intensive exercise is performed for long durations,it can negatively affect the cardiovascular system.We evaluated the exercise-induced physiological responses of cardiac markers in male marathon runners based on basal plasma trimethylamine-N-oxide(TMAO)levels,a metabolite related to major adverse cardiovascular events.Methods:Blood samples from 28 marathon runners were collected two weeks before the marathon run(baseline),after finishing the race(post-marathon),and two weeks after the race(2 weeks post-marathon).Serum cardiac troponin I(c Tn I),endothelin-1(ET-1),galectin-3,pentraxin-3,human growth differentiation factor 15,and neopterin were determined by the enzyme immunoassay method.Plasma trimethylamine(TMA)and TMAO were measured by the ultra-high-performance liquid chromatography-mass spectrometry method.Results:Running a marathon increased levels of circulating biomarkers.A greater post-marathon elevation of cTn I and ET-1 was associated with baseline plasma TMAO levels(R=0.400,p=0.035 and R=0.476,p=0.012,respectively).Moreover,we observed an increase in post-marathon TMA levels.Conclusion:Greater post-marathon elevation of cTn I and ET-1 was associated with higher baseline plasma TMAO levels.Therefore,TMAO could potentially serve as a new marker in assessing the response of cardiovascular stress biomarkers to marathon running.
