Objectives:The aim of this study was to compare the measured physiological factors that limit running performance with real marathon results from world-class distance runners,evaluating the compatibility between measu...Objectives:The aim of this study was to compare the measured physiological factors that limit running performance with real marathon results from world-class distance runners,evaluating the compatibility between measured data and predicted results based on the previously suggested model.Methods:Four world-class East African marathon runners(three male,one female)underwent physiological running assessments to predict marathon performance times using a model based on˙V O_(2)peak,percentage of˙V O_(2)peak at the second ventilatory threshold,and running economy.Predictions were then compared to participants’best marathon times.Results:The measured˙V O_(2)peak of the world-class runners was 75.1±2.7 mL/kg/min.The second ventilatory threshold occurred at 85±3%of the peak,with a running economy of 63.7±2.4 mL/kg/min at 19.6±0.9 km/h.The predicted marathon performance time was 2:06:51±0:03:17 h:min:s for the males and 2:17:36 h:min:s for the female.Comparing these predictions to their personal best times,the average difference was 00:55±00:51 min:s(range:00:20-02:08).Conclusions:This research provides laboratory data on world-class road running athletes,reinforcing the link between marathon performance and˙V O_(2)peak,the percentage of˙VO_(2)peak at the second ventilatory threshold,and running economy.The examined athletes had lower˙V O_(2)peak compared to predicted values,highlighting the importance of running economy and fractional utilization of˙V O_(2)peak in achieving such performances.Future studies should continue to advance the field by including additional bioenergetic parameters measured during race conditions and expanding the participant cohort of elite marathoners,encompassing both sexes.展开更多
Introduction:Runners from East Africa including Kenya,Ethiopia and Uganda have dominated middle-and longdistance running events,for almost six decades.This narrative review examines and updates current understanding o...Introduction:Runners from East Africa including Kenya,Ethiopia and Uganda have dominated middle-and longdistance running events,for almost six decades.This narrative review examines and updates current understanding of the factors explaining the dominance of East Africans in distance running from a holistic perspective.Content:The dominance of East African distance runners has puzzled researchers,with various factors proposed to explain their unparalleled success.Four key elements emerge:1)biomechanical and physiological attributes,2)training characteristics,3)psychological motivations,and 4)African diet.Runners from East Africa often exhibit ectomorphic somatotypes,characterized by lean body compositions which lead them to an extraordinary biomechanical and metabolic effciency.Their sociocultural lifestyle,training regimens beginning at a young age with aerobic activities,seem crucial,as well as moderate volume,high-intensity workouts at altitudes ranging from 2,000 to 3,000 m.Psychological factors,including a strong motivation to succeed driven by aspirations for socioeconomic improvement and a rich tradition of running excellence,also contribute significantly.A multifactorial explanation considering these factors,without a clear genetic influence,is nowadays the strongest argument to explain the East African phenomenon.Summary and outlook:To unravel the mystery behind the supremacy of East African runners,it is imperative to consider these multifaceted factors.The predominantly rural lifestyle of the East African population underscores the importance of aligning modern lifestyles with the evolutionary past of Homo sapiens,where physical activity was integral to daily life.Further research is required to explain this phenomenon,with a focus on genetics.展开更多
Purpose To determine the association between lower-body strength and lower-body power capacities with sprint swimming performance in adolescent competitive swimmers.Methods A total of 44 front crawl swimmers(27 males ...Purpose To determine the association between lower-body strength and lower-body power capacities with sprint swimming performance in adolescent competitive swimmers.Methods A total of 44 front crawl swimmers(27 males and 17 females)performed anthropometric assessments,lower-body strength tests(half squat maximum isometric strength,dynamic half squat with 20,30 and 40%of the maximum isometric strength,and knee extension maximum isometric strength)and lower-body power tests(squat jump[SJ],countermovement jump[CMJ]and Abalakov jump).Further front crawl swimming best times in 50 and 100 m were recorded from official swimming competitions and front crawl technique was assessed by an experienced coach using a visual analogue scale.Results Swimming performance was correlated with lower-body power variables(SJ[r=−0.573 for 50 m and−0.642 for 100 m],CMJ[r=−0.497 for 50 m and−0.544 for 100 m],and Abalakov jump[r=−0.452 for 50 m and−0.415 for 100 m];p≤0.05)and lower-body strength(half squat maximum isometric strength[r=−0.430 for 50 m and−0.443 for 100 m];p≤0.05)in males but not in females.Further linear regression models showed that only lower-body power predicted both 50 m(Abalakov jump;r^(2)=0.58;change in r^(2)=0.18)and 100 m(SJ;r^(2)=0.66;change in r^(2)=0.15)performance in male swimmers.Conclusions This study emphasizes the greater association between lower-body power and sprint front crawl performance in adolescent males compared to females.Practical tests(i.e.,SJ and Abalakov jump)are shown to predict front crawl swimming performance,which may facilitate the performance control by coaches and trainers.展开更多
Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods T...Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods Thirty-two recreational runners(age:38.7±10.2 years,mass:73.9±11.0 kg,height:177±8 cm)were invited to participate in this study.Core temperature was continuously assessed using telemetric ingestible pills.Each runner swallowed two pills:the first pill(Pill 1)11 h:47 min±1 h:01 min pre-race(before overnight sleep)and the second(Pill 2)2 h:35 min±0 h:54 min pre-race(on wakening).Results Pre-race core temperature for Pill 1 was significantly different from Pill 2,with values of 37.4±0.4℃and 37.1±0.6℃,respectively(p=0.006).The mean core temperature during the race was higher for Pill 1 compared to Pill 2(38.5±0.5℃and 37.8±1.0℃,respectively;p<0.001).Peak core temperature was higher for Pill 1 compared to Pill 2(39.1±0.5℃and 38.8±0.5℃,respectively;p=0.03).Post-race core temperature was higher for Pill 1 compared to Pill 2(38.8±0.7℃and 38.1±1.3℃,respectively;p=0.02).Conclusions The timing of pill ingestion significantly impacted core temperature and hence timing of pill ingestion should be standardised(5 h:30 min–7 h prior to measurement).Despite the relatively cool ambient conditions during the race,a significant number of runners achieved a high core body temperature(≥39℃),which was not accompanied by any signs of heat illness.展开更多
Objectives The purpose of this study is to examine the effects of applying anodal tDCS(2 mA for 20 min)over the scalp from T3(anodal-tDCS)to Fp2(cathodal-tDCS)on the perceptual,physiological and performance responses ...Objectives The purpose of this study is to examine the effects of applying anodal tDCS(2 mA for 20 min)over the scalp from T3(anodal-tDCS)to Fp2(cathodal-tDCS)on the perceptual,physiological and performance responses during maximal incremental and constant-load exercise(CLE)in trained cyclists.Methods Eleven male cyclists performed maximal incremental exercise(MIE)on a cycle ergometer under either tDCS or sham,with power output,heart rate(HR),oxygen uptake(V̇O_(2)),ratings of perceived exertion(RPE)assessed throughout,and blood samples collected before and after MIE.On two separate occasions,nine subjects performed CLE at 62%of the peak power output followed by a 15 km time trial under either tDCS or sham(n=8 for the time trial).Results HR,V̇O_(2),RPE and blood samples were collected at regular intervals.There were no differences between tDCS and sham in any variable during the MIE.tDCS elicited a decreased HR(F_(4,8)=9.232;p=0.016;η_(p)^(2)=0.54),increased V̇O_(2)(F_(4,8)=8.920;p=0.015;η_(p)^(2)=0.50)and increased blood non-esterified fatty acids(F_(6,8)=11.754;p=0.009;η_(p)^(2)=0.60)and glycerol(F_(6,8)=6.603;p=0.037;η_(p)^(2)=0.49)concentrations during the CLE when compared to sham.tDCS also improved 15 km time trial performance by 3.6%(p=0.02;d=0.47)without affecting RPE,HR and blood lactate.Conclusions The application of tDCS over the temporal cortex in trained cyclists improved cycling performance during a self-paced time trial but did not enhance performance during maximal incremental exercise.These results are encouraging and merit further investigation of the ergogenic effects of tDCS in trained athletes.展开更多
基金supported by adidas AG.MJ was not compensated for his contribution to this work.
文摘Objectives:The aim of this study was to compare the measured physiological factors that limit running performance with real marathon results from world-class distance runners,evaluating the compatibility between measured data and predicted results based on the previously suggested model.Methods:Four world-class East African marathon runners(three male,one female)underwent physiological running assessments to predict marathon performance times using a model based on˙V O_(2)peak,percentage of˙V O_(2)peak at the second ventilatory threshold,and running economy.Predictions were then compared to participants’best marathon times.Results:The measured˙V O_(2)peak of the world-class runners was 75.1±2.7 mL/kg/min.The second ventilatory threshold occurred at 85±3%of the peak,with a running economy of 63.7±2.4 mL/kg/min at 19.6±0.9 km/h.The predicted marathon performance time was 2:06:51±0:03:17 h:min:s for the males and 2:17:36 h:min:s for the female.Comparing these predictions to their personal best times,the average difference was 00:55±00:51 min:s(range:00:20-02:08).Conclusions:This research provides laboratory data on world-class road running athletes,reinforcing the link between marathon performance and˙V O_(2)peak,the percentage of˙VO_(2)peak at the second ventilatory threshold,and running economy.The examined athletes had lower˙V O_(2)peak compared to predicted values,highlighting the importance of running economy and fractional utilization of˙V O_(2)peak in achieving such performances.Future studies should continue to advance the field by including additional bioenergetic parameters measured during race conditions and expanding the participant cohort of elite marathoners,encompassing both sexes.
文摘Introduction:Runners from East Africa including Kenya,Ethiopia and Uganda have dominated middle-and longdistance running events,for almost six decades.This narrative review examines and updates current understanding of the factors explaining the dominance of East Africans in distance running from a holistic perspective.Content:The dominance of East African distance runners has puzzled researchers,with various factors proposed to explain their unparalleled success.Four key elements emerge:1)biomechanical and physiological attributes,2)training characteristics,3)psychological motivations,and 4)African diet.Runners from East Africa often exhibit ectomorphic somatotypes,characterized by lean body compositions which lead them to an extraordinary biomechanical and metabolic effciency.Their sociocultural lifestyle,training regimens beginning at a young age with aerobic activities,seem crucial,as well as moderate volume,high-intensity workouts at altitudes ranging from 2,000 to 3,000 m.Psychological factors,including a strong motivation to succeed driven by aspirations for socioeconomic improvement and a rich tradition of running excellence,also contribute significantly.A multifactorial explanation considering these factors,without a clear genetic influence,is nowadays the strongest argument to explain the East African phenomenon.Summary and outlook:To unravel the mystery behind the supremacy of East African runners,it is imperative to consider these multifaceted factors.The predominantly rural lifestyle of the East African population underscores the importance of aligning modern lifestyles with the evolutionary past of Homo sapiens,where physical activity was integral to daily life.Further research is required to explain this phenomenon,with a focus on genetics.
基金funded by Spanish‘Ministerio de Economía y Competitividad’‘Plan Nacional I+D+i 2008–2011(Project DEP DEP2011-29093)’and the“Fondo Europeo de Desarrollo Regional”(MICINN-FEDER)for supporting this project.
文摘Purpose To determine the association between lower-body strength and lower-body power capacities with sprint swimming performance in adolescent competitive swimmers.Methods A total of 44 front crawl swimmers(27 males and 17 females)performed anthropometric assessments,lower-body strength tests(half squat maximum isometric strength,dynamic half squat with 20,30 and 40%of the maximum isometric strength,and knee extension maximum isometric strength)and lower-body power tests(squat jump[SJ],countermovement jump[CMJ]and Abalakov jump).Further front crawl swimming best times in 50 and 100 m were recorded from official swimming competitions and front crawl technique was assessed by an experienced coach using a visual analogue scale.Results Swimming performance was correlated with lower-body power variables(SJ[r=−0.573 for 50 m and−0.642 for 100 m],CMJ[r=−0.497 for 50 m and−0.544 for 100 m],and Abalakov jump[r=−0.452 for 50 m and−0.415 for 100 m];p≤0.05)and lower-body strength(half squat maximum isometric strength[r=−0.430 for 50 m and−0.443 for 100 m];p≤0.05)in males but not in females.Further linear regression models showed that only lower-body power predicted both 50 m(Abalakov jump;r^(2)=0.58;change in r^(2)=0.18)and 100 m(SJ;r^(2)=0.66;change in r^(2)=0.15)performance in male swimmers.Conclusions This study emphasizes the greater association between lower-body power and sprint front crawl performance in adolescent males compared to females.Practical tests(i.e.,SJ and Abalakov jump)are shown to predict front crawl swimming performance,which may facilitate the performance control by coaches and trainers.
文摘Objectives The purpose was to directly assess in-competition thermoregulatory responses in recreational runners during a city marathon conducted in cool,ambient conditions using a two-pill ingestion strategy.Methods Thirty-two recreational runners(age:38.7±10.2 years,mass:73.9±11.0 kg,height:177±8 cm)were invited to participate in this study.Core temperature was continuously assessed using telemetric ingestible pills.Each runner swallowed two pills:the first pill(Pill 1)11 h:47 min±1 h:01 min pre-race(before overnight sleep)and the second(Pill 2)2 h:35 min±0 h:54 min pre-race(on wakening).Results Pre-race core temperature for Pill 1 was significantly different from Pill 2,with values of 37.4±0.4℃and 37.1±0.6℃,respectively(p=0.006).The mean core temperature during the race was higher for Pill 1 compared to Pill 2(38.5±0.5℃and 37.8±1.0℃,respectively;p<0.001).Peak core temperature was higher for Pill 1 compared to Pill 2(39.1±0.5℃and 38.8±0.5℃,respectively;p=0.03).Post-race core temperature was higher for Pill 1 compared to Pill 2(38.8±0.7℃and 38.1±1.3℃,respectively;p=0.02).Conclusions The timing of pill ingestion significantly impacted core temperature and hence timing of pill ingestion should be standardised(5 h:30 min–7 h prior to measurement).Despite the relatively cool ambient conditions during the race,a significant number of runners achieved a high core body temperature(≥39℃),which was not accompanied by any signs of heat illness.
文摘Objectives The purpose of this study is to examine the effects of applying anodal tDCS(2 mA for 20 min)over the scalp from T3(anodal-tDCS)to Fp2(cathodal-tDCS)on the perceptual,physiological and performance responses during maximal incremental and constant-load exercise(CLE)in trained cyclists.Methods Eleven male cyclists performed maximal incremental exercise(MIE)on a cycle ergometer under either tDCS or sham,with power output,heart rate(HR),oxygen uptake(V̇O_(2)),ratings of perceived exertion(RPE)assessed throughout,and blood samples collected before and after MIE.On two separate occasions,nine subjects performed CLE at 62%of the peak power output followed by a 15 km time trial under either tDCS or sham(n=8 for the time trial).Results HR,V̇O_(2),RPE and blood samples were collected at regular intervals.There were no differences between tDCS and sham in any variable during the MIE.tDCS elicited a decreased HR(F_(4,8)=9.232;p=0.016;η_(p)^(2)=0.54),increased V̇O_(2)(F_(4,8)=8.920;p=0.015;η_(p)^(2)=0.50)and increased blood non-esterified fatty acids(F_(6,8)=11.754;p=0.009;η_(p)^(2)=0.60)and glycerol(F_(6,8)=6.603;p=0.037;η_(p)^(2)=0.49)concentrations during the CLE when compared to sham.tDCS also improved 15 km time trial performance by 3.6%(p=0.02;d=0.47)without affecting RPE,HR and blood lactate.Conclusions The application of tDCS over the temporal cortex in trained cyclists improved cycling performance during a self-paced time trial but did not enhance performance during maximal incremental exercise.These results are encouraging and merit further investigation of the ergogenic effects of tDCS in trained athletes.
