The purpose of this study was to examine the effect of 4 weeks of intense interval-training on the pulmonary off-transient oxygen uptake (V*O2) after running until exhaustion at the same absolute speed. Seven physical education students ran as follows in three maximal tests on a synthetic track (400 m) whilst ...

There is a wide body of literature reporting red cell hemolysis as occurring after various forms of exercise. Whereas the trauma associated with footstrike is thought to be the major cause of hemolysis after running, its significance compared with hemolysis that results from other circulatory stresses on the red blood ...

PURPOSE: To determine whether the stiffness characteristics of the leg change during a treadmill run to voluntary exhaustion. METHODS: Fifteen runners performed a test run at a constant speed that elicited approximately 80% of their .VO(2peak). The run was performed on a treadmill instrumented to measure vertical ground reaction forces; ...

PURPOSE: The purpose of this study was to examine the effects of specific inspiratory muscle training (IMT) on respiratory muscle strength and endurance and whole-body endurance exercise capacity in competitive endurance athletes. METHODS: Seven collegiate distance runners (5 male/2 female; VO2max = 59.9 +/- 11.7 mL.kg-1.min-1) were recruited to participate ...

This study examined the effect of 8 weeks of specific marathon training before the Olympic trials on the physiological factors of the marathon performance in top-class marathon runners. Five males and four females, age 34 +/- 6 yr (+/- SD) with a marathon performance time of 2 h 11 min ...

The purpose of this study was to investigate the influence of midsole durometer on mechanical and hematological responses during a prolonged downhill run. Twenty-four men completed a 30-min downhill run (-12% grade) wearing either soft, medium, or hard midsole shoes. Data describing mean peak tibial acceleration (PTA), stride frequency, plasma ...

PURPOSE: To examine the kinematic adjustments that runners make during an exhaustive run and to look at the effects these adjustments have on shock and shock attenuation. METHODS: Ten recreational runners ran to volitional exhaustion on a treadmill at a velocity equal to their average 3200-m running velocity at maximal ...

The cholecystokinin (CCK) system, which has been shown to interact with both the panicogenic and respiratory systems, provides an interesting mechanism to further evaluate the central chemoreceptor and its effect on panic attack sensitivity. Intravenous CCK, a naturally occurring neuropeptide in the brain, has been found to induce the emotional ...

This study evaluated whether the heart rate (HR) response to exercise depends on body position and on the active muscle mass. The HR response to ergometer rowing (sitting and using both arms and legs) was compared to treadmill running (upright exercise involving mainly the legs) using a progressive exercise intensity ...

This study was designed to determine the intermittent critical velocity, the time spent at maximal oxygen uptake (VO2max) and the time spent above 90% of VO2max for short intermittent runs of 15 s at supramaximal velocities, alternating with 15 s of passive recovery. Nine male subjects performed 5 field-tests to ...

Blood chemical parameters were analyzed by Fourier-transform infrared spectrometry (notably for determining the concentrations of glucose, lactate, urea, glycerol, triglycerides, and proteins) in 14 top-class marathon runners (133.7+/-4.1 min at marathon, 10.1% difference between extremes) who performed a 10-km run at their individual marathon velocity. Marathon performance level was correlated ...

Best performances in middle-distance running are characterized by coefficients of variation of the velocity ranging from 1% to 5%. This seems to suggest that running at constant velocity is a strain inducing an increase in physiological variables such as oxygen uptake. This study tested three questions. (l) Does velocity variability ...

We employed an associative learning paradigm to test the hypothesis that exercise hyperpnea in humans arises from learned responses forged by prior experience. Twelve subjects undertook a "conditioning" and a "nonconditioning" session on separate days, with order of performance counterbalanced among subjects. In both sessions, subjects performed repeated bouts of ...

Jim Fixx was one of millions ofAmericans who started running in the 1 960s, 1970s, and 1980s. Unlike other runners, however, Fixx wrote a best-selling book about running and, ironically, died of a heart attack at the age of 52 years while running. Fixx and the authors of other running ...

PURPOSE: The purpose of this study was to investigate the influence of different cycling cadences on metabolic and kinematic parameters during subsequent running. METHODS: Eight triathletes performed two incremental tests (running and cycling) to determine maximal oxygen uptake (VO2max) and ventilatory threshold (VT) values, a cycling test to assess the ...

The Access bar claims to contain adenosine antagonists and a precise mixture of macronutrients that are purported to improve aerobic performance by increasing fat metabolism and providing sustained exogenous energy. The purpose of this research was to examine the effect of the Access bar on endurance running performance. Twelve active, ...

This study investigated the effects of 40-weeks training in swimming, cycling and running on performances in swimming, running and triathlon competitions in four elite triathletes. The training stimulus was calculated using the exercise heart rate. The level of performance was measured in running by a submaximal 30 min run, in ...

To examine correlates of the speed at which female soldiers carrying loads could cover 3.2 km on foot and traverse an obstacle course, 12 volunteers (mean +/- SD: 25.3 +/- 6 years, 166 +/- 7 cm, 61.3 +/- 7 kg) were timed over 3.2 km while carrying loads of 14, ...

Exercise-induced impairment in blood fluidity has been supposed to increase cardiovascular risk but there is no data to support this hypothesis. We report the case of a 50 yr old marathon runner who underwent a central retinal vein thrombosis after a marathon run. We investigated his rheological response to exercise ...

The purpose of this study was to examine whether an over-stimulation of the vestibular system, induced by thousands of time saccadic head stimulations, affects the vestibular sensitivity, and consequently if such a phenomenon could contribute to the deterioration of postural stability observed after a long distance running exercise. Eighteen athletic ...

OBJECTIVES: The purpose of this study was to determine the effect of performance level on the pulmonary responses in triathletes during the cycle-run succession. METHODS: Eight regionally and nationally ranked (Competitive) and six internationally ranked (Elite) male triathletes underwent 30 min of cycling followed by 20 min of running (C-R) ...

BACKGROUND: In the present study, vastus lateralis de-oxygenation was monitored contemporarily with VO2 changes along a severe constant intensity running exercise, after the 3rd min up to volitional exhaustion. Blood lactate accumulation was also measured before, during and after running. METHODS: Eleven male amateur soccer players volunteered for the study. ...

The aim of the present study was to examine the effect of increased arousal induced by a prolonged exercise at ventilatory threshold simple reaction time performance performed during a running task. 11 well trained triathletes completed two testing sessions within a 2-wk. period. The first session was a protocol of ...

Rat genetic models of intrinsic (i.e., untrained) low-capacity runners (LCR) and high-capacity runners (HCR) are being developed by artificial selective breeding for treadmill running. At generation 3, these lines differed in running capacity by 114%. We used generation 3 rats to test the hypotheses that HCR, relative to LCR, have ...

The purpose of this study was to determine whether a low-volume high-intensity resistance training session influenced running economy during a subsequent aerobic treadmill run. Nine well trained distance runners (mean +/- SD; VO2max, 66.6 +/- 10.2 ml x kg(-1) x min(-1); weight, 65.8 +/- 10.2 kg; height, 173.4 +/- 7.8 ...

The aim of the present study was to investigate the relationship between alterations in pulmonary function (i.e., diffusing capacity for carbon monoxide and pulmonary volumes) and the ventilatory response elicited during the cycle-run succession in triathletes. Ten well-trained triathletes performed three exercises: 1) 30 min cycling plus 20 min of ...

PURPOSE: This study compares the physical and training characteristics of top-class marathon runners (TC), i.e., runners having a personal best of less than 2 h 11 min for males and 2 h 32 min for females, respectively, versus high-level (HL) (< 2 h 16 min and < 2 h 38 ...

BACKGROUND: We still know relatively little about the factors that define the ability to perform a good run after cycling in triathlon, however, and the perception of discomfort during the first minutes of this post-cycling running has yet to be satisfactorily explained. The pulmonary diffusion capacity for carbon monoxide (DLCO) ...

The present purpose was to study the relationships between perceived exertion (RPE, ETL) and exercise duration for all-out runs eliciting vVO2 max. 12 endurance-trained men performed three exhausting exercises on an indoor track. The first test was an incremental exercise to measure their maximal oxygen uptake (VO2 max), the velocity ...

PURPOSE: This study tested the hypothesis that free versus constant pace enhanced the performance (i.e., distance run) in suprathreshold runs between 90 and 105% of the velocity associated with the maximal oxygen consumption determined in an incremental test (v.VO(2max)). Moreover, we hypothesized that variable pace could decrease the slow phase ...

To examine the activity profile and physiological demands of top-class soccer refereeing, we performed computerized time-motion analyses and measured the heart rate and blood lactate concentration of 27 referees during 43 competitive matches in the two top Danish leagues. To relate match performance to physical capacity and training, several physiological ...

This study examined the effects of heat stress on the accumulation of plasma ammonia, lactate, and urate during prolonged running. Nine highly trained endurance runners completed two running trials in a counterbalanced fashion in cool (15 degrees C) and in hot (35 degrees C) humid (60% relative humidity) conditions. Subjects ...

The aim of this study was to test the hypothesis that the self selected speed in running (vss) is dependent upon the same factors that determine maximal speed in endurance events (e. g. the anaerobic threshold). Experiments were carried out on 8 recreational long distance runners (42.1 +/- 8.6 years ...

Stroke volume (SV) responses during graded treadmill exercise were studied in 1) elite male distance runners (N = 5), 2) male university distance runners (N = 10), and 3) male untrained university students (N = 10). METHODS: Cardiac output (Q) and SV were determined by a modified acetylene rebreathing procedure. ...

Three experiments tested the hypothesis that habituation contributes to the regulation of wheel running. Rats ran in a wheel for 30-min sessions. Experiment 1 demonstrated spontaneous recovery. Rats ran more and the within-session decreases in running were smaller after 2 days of wheel deprivation than after 1 day. Experiment 2 ...

Research demonstrates an inverse relationship between the range of motion of selected joint movements (flexibility) and running economy. Since stretching exercises have been shown to increase joint range of motion, stretching exercises may be contraindicated for endurance running performance. Hence, this study investigated the influence of a 10-week program of ...

BACKGROUND: Exercise-related gastrointestinal symptoms are not uncommon among athletes. The occurrence of gastrointestinal bleeding has been reported, especially in long-distance runners. We studied gastrointestinal mucosal damage, using gastrointestinal endoscopy, in competitive long-distance runners. Gastrointestinal blood loss and anaemia before and after running were also assessed. METHODS: Sixteen competitive long-distance runners ...

BACKGROUND: The purpose of the present study was to investigate changes in physiological, metabolic and performance parameters resulting from an intense 6 week training programme. METHODS: Sixteen volunteers were divided into a control (CN; 4 men and 2 women) and training group (TR; 6 men and 4 women). Laboratory measures ...

BACKGROUND: This study was designed to determined the pulmonary responses elicited by multi-cycle-run exercise in triathletes and to compare them to those elicited during a simple cycle-run succession. METHODS: Twelve male triathletes underwent three successive laboratory trials: 1) an incremental cycle test, 2) 30 min of cycling followed by 20 ...

Levels of alpha-tocopherol (alphaT) in plasma and red blood cells (RBC) are assumed to be modulated by exercise. The mechanisms involved remain to be established. We examined the influence of different running bouts on the content of alphaT in RBC (alphaT(RBC)), the concentration in plasma (alphaTplasma), and their relationship with ...

BACKGROUND: Non-experienced triathletes use to complain about the difficulty to run after cycling. We tested the hypothesis that elite triathletes have lower and/or shorter alterations in running mechanics following a maximal cycling exercise than their less efficient counterparts. METHODS: The mechanical alterations in running after exhaustive cycling exercise were studied ...

BACKGROUND: This study examines the fitness level of a rhythmic gymnasts group and a young female classical dancers group. METHODS: Aerobic power (VO2max), individual ventilatory (IVT) and anaerobic thresholds (IAT) were assessed in 12 elite rhythmic gymnasts, eight elite ballet dancers and 12 sedentary female subjects in the same age ...

It was hypothesized that certain ground reaction force (GRF) variables are positively correlated with running economy (RE; the aerobic demand at a single speed of running). Excessive momentum changes, quantified by linear impulse measures, as well the free moment applied to the running surface could be considered potentially wasteful efforts ...

The chronic exposure of astronauts to microgravity results in structural degradation of their lower limb bones. Currently, no effective exercise countermeasure exists. On Earth, the impact loading that occurs with regular locomotion is associated with the maintenance of bone's structural integrity, but impact loads are rarely experienced in space. Accurately ...

The effects of different grades of running on esophageal motility and gastroesophageal reflux in the fed state were evaluated. We studied healthy volunteers (male: 12, age: 27 +/- 5 yr) using ambulatory esophageal manometry, pH catheter and portable digital data recorder. Each exercise was performed 30 min after meal, with ...

The aim of this study was to determine the effect of endurance training on the relationship between mechanical stride descriptors (stride rate and stride rate variability) and the aerobic energy cost that would be decreased by training in an all-out supra-lactate threshold run. Six long distance runners (175 +/- 6 ...

Deep water running (DWR) has become a well-recognized from of cardiovascular conditioning for injured athletes and has been used successfully to maintain running performance. DWR provides for decreased stress and weightbearing to injured tissue and joints, allows for maintenance of cardiovascular fitness and a training effect, and offers greater specificity ...

BACKGROUND: The main purpose of this study was to test the effects of a duathlon competition on running economy. METHODS. EXPERIMENTAL DESIGN: A prospective study. SETTING: University. Participants: nine male and six female physical education students, which mean (SEM) age was 24.0 (1.3) years. MEASURES: Subjects participated in two competitive ...

PURPOSE: The purposes of this study were first to compare the physiological responses during a triathlon where cycling was performed alternatively with another cyclist (alternate draft triathlon, ADT) or continuously behind him (continuous draft triathlon, CDT), and second to study the incidence of these two drafting modalities in cycling on ...

OBJECTIVE: To assess MRI changes in the ankle and foot after physical exercise. DESIGN AND PATIENTS: Nineteen non-professional marathon runners and 19 age- and sex-matched controls volunteered for the study. All had ankle and foot MR images (1.5 T) taken in three perpendicular planes (STIR, T2F and T1FS sequences) within ...