SEARCH · PubMed Health

Results for “Running”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

PubMed1990

Peak treadmill running velocity during the VO2 max test predicts running performance.

Twenty specialist marathon runners and 23 specialist ultra-marathon runners underwent maximal exercise testing to determine the relative value of maximum oxygen consumption (VO2max), peak treadmill running velocity, running velocity at the lactate turnpoint, VO2 at 16 km h-1, % VO2max at 16 km h-1, and running time in other races, for predicting performance in races of 10-90 km. Race time at 10 or 21.1 km was the best predictor of performance at 42.2 km in specialist marathon runners and at 42.2 and 90 km in specialist ultra-marathon runners (r = 0.91-0.97). Peak treadmill running velocity was the best laboratory-measured predictor of performance (r = -0.88(-)-0.94) at all distances in ultra-marathon specialists and at all distances except 42.2 km in marathon specialists. Other predictive variables were running velocity at the lactate turnpoint (r = -0.80(-)-0.92); % VO2max at 16 km h-1 (r = 0.76-0.90) and VO2max (r = 0.55(-)-0.86). Peak blood lactate concentrations (r = 0.68-0.71) and VO2 at 16 km h-1 (r = 0.10-0.61) were less good predictors. These data indicate: (i) that in groups of trained long distance runners, the physiological factors that determine success in races of 10-90 km are the same; thus there may not be variables that predict success uniquely in either 10 km, marathon or ultra-marathon runners, and (ii) that peak treadmill running velocity is at least as good a predictor of running performance as is the lactate turnpoint. Factors that determine the peak treadmill running velocity are not known but are not likely to be related to maximum rates of muscle oxygen utilization.

Adult↗

PubMed2001

Swing- and support-related muscle actions differentially trigger human walk-run and run-walk transitions.

There has been no consistent explanation as to why humans prefer changing their gait from walking to running and from running to walking at increasing and decreasing speeds, respectively. This study examined muscle activation as a possible determinant of these gait transitions. Seven subjects walked and ran on a motor-driven treadmill for 40s at speeds of 55, 70, 85, 100, 115, 130 and 145% of the preferred transition speed. The movements of subjects were videotaped, and surface electromyographic activity was recorded from seven major leg muscles. Resultant moments at the leg joints during the swing phase were calculated. During the swing phase of locomotion at preferred running speeds (115, 130, 145%), swing-related activation of the ankle, knee and hip flexors and peaks of flexion moments were typically lower (P<0.05) during running than during walking. At preferred walking speeds (55, 70, 85%), support-related activation of the ankle and knee extensors was typically lower during stance of walking than during stance of running (P<0.05). These results support the hypothesis that the preferred walk-run transition might be triggered by the increased sense of effort due to the exaggerated swing-related activation of the tibialis anterior, rectus femoris and hamstrings; this increased activation is necessary to meet the higher joint moment demands to move the swing leg during fast walking. The preferred run-walk transition might be similarly triggered by the sense of effort due to the higher support-related activation of the soleus, gastrocnemius and vastii that must generate higher forces during slow running than during walking at the same speed.

Adult↗

PubMed2003

Responding for sucrose and wheel-running reinforcement: effects of sucrose concentration and wheel-running reinforcer duration.

Six male albino rats were placed in running wheels and exposed to a fixed-interval 30-s schedule of lever pressing that produced either a drop of sucrose solution or the opportunity to run for a fixed duration as reinforcers. Each reinforcer type was signaled by a different stimulus. In Experiment 1, the duration of running was held constant at 15 s while the concentration of sucrose solution was varied across values of 0, 2.5. 5, 10, and 15%. As concentration decreased, postreinforcement pause duration increased and local rates decreased in the presence of the stimulus signaling sucrose. Consequently, the difference between responding in the presence of stimuli signaling wheel-running and sucrose reinforcers diminished, and at 2.5%, response functions for the two reinforcers were similar. In Experiment 2, the concentration of sucrose solution was held constant at 15% while the duration of the opportunity to run was first varied across values of 15, 45, and 90 s then subsequently across values of 5, 10, and 15 s. As run duration increased, postreinforcement pause duration in the presence of the wheel-running stimulus increased and local rates increased then decreased. In summary, inhibitory aftereffects of previous reinforcers occurred when both sucrose concentration and run duration varied; changes in responding were attributable to changes in the excitatory value of the stimuli signaling the two reinforcers.

Animals↗

PubMed1988

Free-access to a running wheel shortens the period of free-running rhythm in blinded rats.

The period of free-running rhythm was measured with two different devices, Automex and running wheel, in blinded female rats. The period was significantly shorter when measured with a running wheel than with an Automex. After transfer between the two devices, all 13 rats examined showed the same direction of change in the free-running period and that transfer from the Automex to running wheel shortened the period, while transfer from the running wheel to Automex elongated it, with the exception of two rats who did not show any significant change in the period even when they were transferred twice. These results indicate that free access to a running wheel shortens the free-running period in female blinded rats.

Animals↗

PubMed1991

Motor activity correlates negatively with free-running period, while positively with serotonin contents in SCN in free-running rats.

Free-running period of blinded rats kept in a cage with a running wheel varied markedly, while it varied little in rats kept in a cage without a running wheel. The mean free-running period of the former group is significantly shorter than that of the latter. In the former, the free-running period correlated negatively with motor activity, indicating that activity affects the free-running period. In both groups, essentially similar diurnal patterns of biogenic amines and their metabolites were observed in various discrete areas in the brain examined. However, there was a significant difference between the two groups in several areas. In the SCN, 5-HT content correlated positively with motor activity, consequently correlated negatively to the free-running period at 3 out of 4 sampling times over 24 h but no such correlation was observed in other monoamines and their metabolites examined. These facts suggest that 5-HT may be associated with modification of the free-running period.

Animals↗

PubMed1999

Body composition, resting and running metabolic rates, and net cost of running in rats during starvation.

Resting metabolic rate decreases during starvation. However, effects of starvation on the cost of running are not clear. The aim of this study was to examine the effects of 5 days starvation on body composition, resting metabolic rates, running metabolic rates, and net cost of running in male rats. Five days starvation resulted in reductions of 70% fat, 8% protein and 12% carbohydrates. Mass(-0.75) specific resting metabolic rate was significantly reduced from 3.69 +/- 0.27 to 2.73 +/- 0.17 W kg(-0.75) after 5 days starvation. The reduction in metabolic rate after 5 days starvation was maintained during running, in that running metabolic rate was reduced from 10.65 +/- 0.41 to 8.97 +/- 0.47 W kg(-0.75). The net costs of running were calculated and expressed as the costs of moving 1 kg a distance of 1 m. After 5 days of starvation it was reduced from 31.16 +/- 2.03-29.79 +/- 1.69 J m(-1) kg(-1). The reduction however was not significant. The present results therefore suggest that 5 days starvation resulted in a metabolic depression of the resting metabolic rate that was maintained during running. However, the net cost of running remained unchanged, suggesting that the muscle tissues are not significantly involved in the metabolic changes during starvation.

Animals↗

PubMed2003

Keratometric astigmatism after suture removal in penetrating keratoplasty: double running versus single running suture techniques.

BACKGROUND AND OBJECTIVE: To compare astigmatism after suture removal in a retrospective sequential series of patients who had penetrating keratoplasty with either a double running suture technique or an adjustable single running suture technique. During the first year postkeratoplasty, when sutures were in place, the latter technique had produced less astigmatism. MATERIALS AND METHODS: Keratometry and keratometric astigmatism were measured before and after suture removal. We compared these variables in 30 grafts with the double running suture technique to the same variables in 24 grafts with the single running suture technique. RESULTS: The final portion of the double running suture was removed 408 +/- 177 (mean +/- SD) days after keratoplasty, whereas the single running suture was removed 611 +/- 224 days after keratoplasty (P<0.001). After suture removal, there was no difference between the double running and single running groups in either mean keratometry [46.5 +/- 1.8 diopters (D) versus 45.6 +/- 2.0 D, P=0.09, minimum detectable difference (MDD)=1.5D] or mean astigmatism (4.6 +/- 2.7 D versus 5.2 +/- 3.2D, P=0.72, MDD=2.3). CONCLUSION: In this consecutive series of corneal transplants performed by one surgeon, the results suggest no difference in astigmatism between the two suturing techniques after all sutures have been removed.

Astigmatism↗

PubMed1990

Spontaneous running increases VO2max and running performance in rats.

The effect of spontaneous running activity on maximal O2 consumption (VO2max), running performance, and submaximal O2 consumption (VO2submax, running economy) was studied in rats to determine whether this exercise mode can produce significant training adaptations. Twenty male Long-Evans rats (300 +/- 20 g) were housed in spontaneous activity running wheels, and after 8 wk they were divided into high-, average-, and low-performing groups according to the average spontaneous running distance and tested for maximal running performance, VO2max, and VO2submax. The average-performing rats ran 52% longer than the control rats (P less than 0.01) and 19% longer than the low-performing rats (P less than 0.05). There was no difference in maximum running time to exhaustion between the average- and high-performing rats. The low-performing rats ran 28% longer than the control rats (P less than 0.05). The VO2max of the average-performing rats was 12% greater than in the control rats (P less than 0.01). There were no differences in VO2max between either low-performing and control rats or between average- and high-performing rats. Although the VO2submax was not different between low-, average-, and high-performing rats, in all three groups it was lower than in the control rats (P less than 0.01). Accordingly, we recommend that only those Long-Evans rats that, on average, spontaneously run greater than 11.6 km/wk for a minimum of 8 wk be considered to have undergone a training effect. Rats that perform poorly can be identified as early as 2 wk after the start of training.

Animals↗

PubMed2001

Scheduled voluntary wheel running activity modulates free-running circadian body temperature rhythms in Octodon degus.

Entrainment of the circadian pacemaker to nonphotic stimuli, such as scheduled wheel-running activity, is well characterized in nocturnal rodents, but little is known about activity-dependent entrainment in diurnal or crepuscular species. In the present study, effects of scheduled voluntary wheel-running activity on circadian timekeeping were investigated in Octodon degus, a hystricomorph rodent that exhibits robust crepuscular patterns of wakefulness. When housed in constant darkness, O. degus exhibited circadian rhythms in wheel-running activity and body temperature (Tb) with an average period length (tau) of 23.39 +/- 0.11 h. When wheel running was restricted to a fixed 2-h schedule every 24 h, tau increased on average 0.39 +/- 0.09 h but did not result in steady-state entrainment. Instead, relative coordination between the fixed running schedule and circadian timing was observed. Tau was greatest when scheduled wheel running occurred at CT 20.5 (0.4 h greater than DD baseline tau). Scheduled running activity also influenced Tb waveform symmetry, reflecting concomitant changes in the circadian activity-rest ratio (alpha:rho). Aftereffects of the scheduled wheel-running paradigm were also observed. In 2 animals, tau lengthened from 23.20 and 23.80 h to 24.14 and 24.15 h, respectively, and remained relatively stable for approximately 1 month during the wheel schedule. Although behavioral activity appears to be a weak zeitgeber in this species, these data suggest that nonphotic stimuli can phase delay the circadian pacemaker in O. degus at similar times of the day as in nocturnal hamsters and mice, and in humans.

Animals↗

PubMed1994

Striatal dopamine turnover during treadmill running in the rat: relation to the speed of running.

To evaluate the physiological action of striatal dopamine (DA) in exercise, rats were trained to run on a straight treadmill. Extracellular DA and its metabolites, dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) were measured by in vivo microdialysis, and striatal tissue tyrosine hydroxylase (TH) activity and monoamine oxidase (MAO) activity were measured using high performance liquid chromatography (HPLC) and spectrophotometer. DA turnover was increased by running, and the increase in DOPAC and HVA was closely related to the speed of running, while the increase in DA had no relationship to the speed. The threshold for the increase in DA, DOPAC, and HVA was between 300 and 660 cm/min. Striatal tissue TH activity was elevated up to 135% of basal values after the rats were trained for 7 days to run at 1800 cm/min. Just after running for 20 min, there was a further increase to 180%. These values became 150% and 90% of basal values at 2 h and 6 h, showing a similar time course as DA detected by microdialysis. MAO-B activity increased up to 160% of basal values after 7 days training but decreased to 130% and 110% just after and 2 h after running, then increased to 145% 6 h after running. MAO-A showed a similar variation as MAO-B. These data suggest that both the synthesis and metabolism of DA have a close relationship with physical exercise and might contribute to adjusting extracellular DA levels within an adequate range in response to exercise intensity.

3,4-Dihydroxyphenylacetic Acid↗

PubMed2006

Taste aversion in rats induced by forced swimming, voluntary running, forced running, and lithium chloride injection treatments.

The present experiment compared the strengths of taste aversion learning in rats induced by forced swimming in a water pool (5, 15, 30, or 60 min), voluntary running in an activity wheel (15, 30, 60, or 120 min), forced running in a motorized wheel (60 min at the speed of 8 m/min), optional running in the apparatus consisting of an activity wheel and a side room (120 min), and a lithium chloride (LiCl, 0.15 M LiCl at 2% of body weight) injection. The rats were given an access to saccharin solution immediately followed by one of the above treatments or simply returned back to the home cages for the control group. On the next 2 days, aversion to the saccharin solution was assessed by two-bottle choice testing between it and tap water. The following results were obtained. (1) The saccharin aversion was a positive function of exercise durations in the forced swimming and voluntary running rats, and the exercise of more than 30 min induced statistically significant saccharin aversion, compared with the control rats. (2) The forced running caused relatively strong saccharin aversion. The group of forced running rats acquired the numerically strongest saccharin aversion on average among all exercised rats. (3) The optional running treatment had little effect. (4) The LiCl injection resulted in the strongest aversion among the all treatments explored here.

Animals↗

PubMed2000

The effect of a sports drink on gastroesophageal reflux during a run-bike-run test.

The effects of different modes of prolonged exercise and different drinks on gastroesophageal reflux and reflux-related symptoms were examined. In a cross-over design seven male triathletes performed two tests at one week intervals (50 min periods of alternately running, cycling and running at 70-75% VO2max), with supplementation of either a conventional sports drink (7% carbohydrates) or tap water. Gastroesophageal reflux (percentage time and number of periods esophageal pH < 4) was measured with an ambulant pH system before, during and after exercise. Percentage reflux time (+/- SEM) during running, cycling, running and recovery was 24.0 +/- 4.6, 8.2 +/- 4.8, 17.6 +/- 8.4 and 11.8 +/- 4.0 with carbohydrates and 7.4 +/- 2.9, 0 +/- 0, 2.4 +/- 1.4 and 0.2 +/- 0.2 with water, respectively. Reflux lasted longer during exercise as compared to the rest situation (5.6 + 1.4%), especially with carbohydrates, and lasted longer with carbohydrates than with water (P < 0.05; Wilcoxon signed rank test). In general, reflux lasted longer during running than during cycling (P < 0.05). Data on the number of reflux periods are concordant to these results. Chest pain was reported by one subject during running with carbohydrates. Heartburn during running was reported by two subjects with water and by one with carbohydrates. In conclusion, physical exercise increases gastroesophageal reflux, dependent on the mode of exercise and beverage used.

Adult↗

PubMed2006

Leg heating and cooling influences running stride parameters but not running economy.

To evaluate the effect of temperature on running economy (RE) and stride parameters in 10 trained male runners (VO2peak 60.8 +/- 6.8 ml . kg (-1) . min (-1)), we used water immersion as a passive temperature manipulation to contrast localised pre-heating, pre-cooling, and thermoneutral interventions prior to running. Runners completed three 10-min treadmill runs at 70 % VO2peak following 40 min of randomised leg immersion in water at 21.0 degrees C (cold), 34.6 degrees C (thermoneutral), or 41.8 degrees C (hot). Treadmill runs were separated by 7 days. External respiratory gas exchange was measured for 30 s before and throughout the exercise and stride parameters were determined from video analysis in the sagittal plane. RE was not affected by prior heating or cooling with no difference in oxygen cost or energy expenditure between the temperature interventions (average VO2 3rd-10th min of exercise: C, 41.6 +/- 3.4 ml . kg (-1) . min (-1); TN, 41.6 +/- 3.0; H, 41.8 +/- 3.5; p = 0.94). Exercise heart rate was affected by temperature (H > TN > C; p < 0.001). During minutes 3 - 5 of running the respiratory-exchange and minute ventilation/oxygen consumption ratios were greater in cold compared with thermoneutral (p < 0.05). Averaged over the full 10 min of exercise, stride length was shorter and stride frequency higher for the C trial compared to TN and H (p < 0.01). Leg temperature manipulation did not influence running economy despite changes in stride parameters that might indicate restricted muscle-tendon elasticity after pre-cooling. Larger changes in stride mechanics than those produced by the current temperature intervention are required to influence running economy.

Adult↗

PubMed1987

Effects of sucrose or caffeine ingestion on running performance and biochemical responses to endurance running.

To elucidate the effects of sucrose or caffeine ingestion on metabolic responses to prolonged exercise and on performance of a finishing spurt after the prolonged exercise, seven male physical education students performed four sets of 30 min running (62%-67% VO2 max) followed by progressive exhaustive running on a treadmill. Before each set, they took 350 ml solution containing either sucrose 23.8 g (97.5 kcal), caffeine 200 mg, or a placebo. The duration of the exhaustive running after sucrose, caffeine, or placebo ingestion was not significantly different. Exhaustion would possibly be attained not by depletion of muscle glycogen but by a decrease in the capacity of muscle cells to produce high tension for anaerobic metabolism. Total energy and energy from carbohydrate combusted during four sets of running were estimated at 1255 kcal and 810 kcal in the sucrose trial, 1271 kcal and 624 kcal in the caffeine trial, and 1248 kcal and 649 kcal in the placebo trial. Judging from the figures above, glycogen sparing during prolonged running seemed to be attained by sucrose ingestion but not by caffeine ingestion. The latter finding would be caused by lower intensity and a larger amount of ingested caffeine. In conclusion, performance of progressive exhaustive running following endurance running for 2 h could not be improved either by sucrose or caffeine ingestion. Glycogen sparing in the muscle, however, was suggested by sucrose ingestion but not by caffeine ingestion.

Adult↗

PubMed1997

Running and responding reinforced by the opportunity to run: effect of reinforcer duration.

The present study investigated the effect of reinforcer duration on running and on responding reinforced by the opportunity to run. Eleven male Wistar rats responded on levers for the opportunity to run in a running wheel. Opportunities to run were programmed to occur on a tandem fixed-ratio 1 variable-interval 30-s reinforcement schedule. Reinforcer duration varied across conditions from 30 to 120 s. As reinforcer duration increased, the rates of running and lever pressing declined, and latency to lever press increased. The increase in latency to respond was consistent with findings that unconditioned inhibitory aftereffects of reinforcement increase with reinforcer magnitude. The decrease in local lever-pressing rates, however, was inconsistent with the view that response strength increases with the duration of the reinforcer. Response rate varied inversely, not directly, with reinforcer duration. Furthermore, within-session data challenge satiation, fatigue, and response deprivation as determinants of the observed changes in running and responding. In sum, the results point to the need for further research with nonappetitive forms of reinforcement.

Animals↗

PubMed1977

[Investigations about the effect of run-training and run-stress on glucose tolerance and insulin secretion with ageing streptozotocin-diabetic rats (author's transl)].

Untrained grown-up and old rats with a mild Streptozotocin-diabetes show in i.v. glucose tolerance test a pathological glucose assimilation and diminished insulin secretion in comparison to control rats of the same age after a maximal run-stress. Trained rats show a different behaviour in glucose tolerance test depending on their age and seriousness of diabetes: Glucose tolerance is improved in grown-up rats with a mild diabetes and unchanged in old rats. Six-week run-training causes a significant deterioration of glucose tolerance in rats with a medium seriously Streptozotocin-diabetes and even leads to death of old rats because of decompensated metabolism. Grown-up rats with a mild diabetes stand run-stress after run-training better than the old ones. No animal with a medium seriously diabetes survives maximal run-stress, old rats don't even survive the slowly increasing run-training. - These results confirm the dualistic effect of muscular work. Metabolism of mild diabetes becomes better through muscular exertion the one of medium diabetes gets worse. Therefore a good effect of run-training is measurable only in grown-up rats not in old ones.

Age Factors↗

PubMed1990

[Energy requirements in women during running on a treadmill and running over terrain].

Running is the most frequently used training method of promoting aerobic efficiency, functional capacity and fitness as well as weight reduction. The energy demand on running expressed indirectly in terms of oxygen consumption correlated with 1 kg body weight (VO2.kg-1) can be established on the basis of the running speed (v) using different nomograms and graphs. These relations are linear within the range of submaximum exertion of training intensity, approximately within the range of 20-90% of maximum oxygen consumption. The relationship between VO2.kg-1 and the running speed generally depends on the sex, age, amount of training practice and on the inherent speed capabilities. Based on the measurements of women of different training practice and age, supplemented with data drawn from literature, the authors established an "average" relationship, independent of age, record of training practice and the speed norm valid for the running carpet in the form of VO2.kg-1 = 2.804. v (km.h-1) + 8.922. The error in determining VO2.kg-1 within the range of the speed of 8-18 km.h-1 is approximately 8% or less. Similarly, using nomograms which facilitate the transfer of the running speed on the running carpet to the outdoor speed, the authors found a general equation for a flat terrain in the form of VO2.kg-1 = 3.359. v + 3.308 which can be used for the speed range of 8-16 km.h-1 with the same error as the one obtained indoors. The above relations can be used for estimating the reactions of the organism to indoor or outdoor exertion with the aim of establishing suitable training exertion intensity.

Adolescent↗

PubMed2003

The effects of a single bout of downhill running and ensuing delayed onset of muscle soreness on running economy performed 48 h later.

Delayed onset of muscle soreness (DOMS) is a common response to exercise involving significant eccentric loading. Symptoms of DOMS vary widely and may include reduced force generating capacity, significant alterations in biochemical indices of muscle and connective tissue health, alteration of neuromuscular function, and changes in mechanical performance. The purpose of the investigation was to examine the effects of downhill running and ensuing DOMS on running economy and stride mechanics. Nine, well-trained distance runners and triathletes participated in the study. Running economy was measured at three relative intensities [65, 75, and 85% of maximal aerobic capacity ( VO(2peak))] before (RE1) and 48 h after (RE2) a 30-min downhill run (-10%) at 70% VO(2peak). Dependent variables included leg muscle soreness, rate of oxygen consumption ( VO(2)), minute ventilation, respiratory exchange ratio, lactate, heart rate, and stride length. These measurements were entered into a two-factor multivariate analysis of variance (MANOVA). The analysis revealed a significant time effect for all variables and a significant interaction (time x intensity) for lactate. The energy cost of locomotion was elevated at RE2 by an average of 3.2%. This was coupled with a significant reduction in stride length. The change in VO(2) was inversely correlated with the change in stride length ( r= -0.535). Lactate was significantly elevated at RE2 for each run intensity, with a mean increase of 0.61 mmol l(-1). Based on these findings, it is suggested that muscle damage led to changes in stride mechanics and a greater reliance on anaerobic methods of energy production, contributing to the change in running economy during DOMS.

Adaptation, Physiological↗