Effects of marathon running on running economy and kinematics (original) (raw)
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European Journal of Applied Physiology and Occupational Physiology, 1996
Following treadmill accommodation and a 3-day period of tapered running, ten well-trained male distance runners [2 maximum oxygen uptake ([702max) = 71.3 ml'kg-1. min-11 performed two 10rain level treadmill runs designed to assess running economy at 90% l?O2m~x. Video recordings were obtained during the last minute of each run to quantify selected gait descriptors. Two to 3 days following the second economy run, each subject completed 30 min of high-intensity (HI) running at 90% VO2m~x. One, 2, and 4 days after the HI run, subjects repeated the 10-min economy runs. Compared to pre HI-run values, no significant change (P > 0.05) in running economy was observed during the post-HI runs. Biomechanical analyses also revealed that running style remained unaltered after the HI run. These results support earlier findings obtained on moderately trained subjects featuring measurement of running economy and gait mechanics at less-demanding intensities and suggest that among well-trained athletes, 30 min of HI running does not elicit an increase in 1/O2 or disrupt gait mechanics over the short term in subsequent distance runs performed at near-maximal speeds.
Nicol et al SJMSS 1991 Effects of marathon fatigue on running kinematics and economy
A group of 8 experienced 20to 35-year-old (mean 30) endurance runners (1 woman and 7 men) volunteered for the experiment. Their sport was either marathon or triathlon. The group weight averaged 68 (59-93) kg and height 177 (168-190) cm. Experimental design The experimental design included different tests repeated for each subject on 2 successive sessions, day 1 and day 2, separated by a period of 4 d. The
Some physiological demands of a half-marathon race on recreational runners
British Journal of Sports Medicine, 1983
The purpose of this study was to assess the physiological demands of a half-marathon race on a group of ten recreational runners (8 men and 2 women). The average running speed was 223.1 ± 22.7 m.mini1 (mean ± SD) for the group and this represented 79 ± 5% V02 max for these runners. There was a good correlation between V02 max and performance time for the race (r = -0.81; p < 0.01) and an even better correlation between running speed equivalent to a blood lactate concentration of 4 mmol.r1 and performance times (r = -0.877; p < 0.01). The blood lactate concentration of 4 of the runners at the end of the race was 5.65 ± 1.42 mmol.rF (mean ± SD) and the estimated energy expenditure for the group was 6.22 M.J. While there was only a poor correlation between total energy expenditure and performance time for the race, the correlation coefficient was improved when the energy expenditure of each individual was expressed in KJ.kg 1 min1 (r = -0.938; p < 0.01).
The Effect of Muscular Endurance on Running Economy
Journal of Strength and Conditioning Research, 2011
Hayes, PR, French, DN, and Thomas, K. The effect of muscular endurance on running economy. J Strength Cond Res 25(9): 2464-2469, 2011-The purpose of this study was to examine the relationship between fatigue-induced changes in running economy (RE) and muscular strength endurance (MSE). Ten well-trained male runners completed 2 runs of the same energy expenditure at 20%D _ VO 2 below LT. In the middle of the experimental condition (high intensity exercise [HIE]), there was a 4-minute block at s _ VO 2 max. The aim of the 4-minute block was to increase RE through fatigue, without inducing exhaustion. The MSE of hip extensors (HEs) and knee flexors (KFs) was assessed by 2 20-second eccentric bouts on an isokinetic dynamometer at 180°Ás 21 . The RE increased after HIE compared to the control condition. Partial correlations found the increase in RE was strongly related with KF MSE (r = 20.709-0.798; p = 0.03-0.01). Greater MSE appeared to confer a fatigue resistant effect, resulting in a smaller increase in RE. The underlying mechanism of the fatigue resistant effect remains to be elucidated. Conditioning work focusing on augmenting eccentric muscular endurance of the legs may offer beneficial adaptations that promote fatigue resistance.
Effects of a 2-Hour Run on Metabolic Economy and Lower Extremity Strength in Men and Women
Journal of Orthopaedic & Sports Physical Therapy, 1998
mong the determinants of successful distance running performance are maximal oxygen , consumption (VO,,,,) , lactate and ventilatory thresholds, lean body mass, and running economy (14). Running economy, described as the oxygen cost of running at a given submaximal speed (ml/m/kg), contributes significantly to distance running performance (6, 7,14). Numerous variables may contribute to running economy. Gender (7). age (15), biomechanics (4), flexibility (12), environmental condition (24), and body temperature (16,25) have been suggested as factors that influence economy. The effect of previous bouts of maximal running on running economy has also been examined. Morgan et al found that a 30-minute maximal run did not affect the oxygen cost of running on subsequent days in men (21). The literature suggests that economy during extended bouts of exercise may be influenced by a number of mechanisms. Hamilton et al showed a pronounced rise in oxygen uptake (VO,), which was preventable with intravenous glucose infusion while cycling for 2 hours (13). An upward T O , drift" during exercise has also been demonstrated in men during treadmill exercise with no fluid replacement (l6,23,26). Nielsen et a1 found that the increased total Changes in running economy, or the oxygen cost of running at a given submaximal speed (ml/m/kg), during prolonged exercise have been well described in men but not in women. Lower extremity strength changes associated with prolonged exercise have never been addressed. We examined changes in running economy and strength following a 2-hour run in eight men and eight women. Knee and hip strength were measured pre-and post-running. Peak oxygen consumption (V02pak) and oxygen consumption at ventilatory threshold were determined. Subjects then ran for 2 hours at an intensity which elicited ventilatory threshold (68.7% vs. 66.6% of VOZpak for men and women, p = 0.5). Water was ingested at a rate of 0.5% of body weight each half hour. Oxygen uptake (V02) and respiratory exchange ratio were measured initially and at 1 and 2 hours. Body weight declined in the men @ = 0.001) but not in the women (p = 0.12). Running economy decreased in the men (p < 0.001) but not in the women @ = 0.084). At 2 hours of running knee flexion and extension strength declined significantly in the men only (effect of gender x time, p < 0.014), but hip flexion, abduction, and adduction strength declined in both genders. Decreased knee extensodflexor strength was evident in men only, while decreased hip strength was independent of gender. We conclude that 2 hours of running produced changes in knee strength and running economy in men only.
Applied Physiology, Nutrition, and Metabolism, 2013
This study assessed the between-test reliability of oxygen cost (O C ) and energy cost (E C ) in distance runners, and contrasted it with the smallest worthwhile change (SWC) of these measures. O C and E C displayed similar levels of within-subject variation (typical error < 3.85%). However, the typical error (2.75% vs 2.74%) was greater than the SWC (1.38% vs 1.71%) for both O C and E C , respectively, indicating insufficient sensitivity to confidently detect small, but meaningful, changes in O C and E C .
Effects of marathon fatigue on running kinematics and economy
Scandinavian Journal of Medicine & Science in Sports, 2007
A group of 8 experienced 20to 35-year-old (mean 30) endurance runners (1 woman and 7 men) volunteered for the experiment. Their sport was either marathon or triathlon. The group weight averaged 68 (59-93) kg and height 177 cm.
International journal of sports medicine, 2000
The effects of the triathlon performance level on the metabolic and mechanical alterations in running after an exhaustive cycling exercise were studied. Eight elite and 18 middle-level triathletes completed two 7 min runs on a treadmill at a velocity corresponding to that sustained during a triathlon before and after maximal cycling exercise. Energy cost of running was quantified during the last minute of each run from the net oxygen uptake. External mechanical cost was quantified during the last minute of each run from displacements of the centre of mass using a kinematic arm. The effect of cycling on the running energy cost differed when comparing the elite (from 4.01+/-0.46 to 3.86+/-0.34J x kg(-1) x m(-1)) and the middle-level triathletes (from 3.67+/-0.37 to 3.76+/-0.39 x kg(-1) x m(-1) (P<0.01). The effect of cycling on the respiratory muscle O2 was more important (P<0.05) for the middle-level (from 120.1+/-27.2 to 166.4+/-47.8 ml x min(-1)) than for elite triathletes (f...
Physiological factors affecting performance in elite distance runners
Acta Kinesiologiae Universitatis Tartuensis, 2016
Running distances from 3000 m to the marathon (42 195 m) are events dominated by energy contribution of the aerobic energy system. The physiological factors that underlie success in these running events are maximal oxygen uptake (VO2max), running economy (RE), the utilization of the maximum oxygen uptake (%VO2max) and velocity at the anaerobic threshold (vAT). VO2max for distance runners competing on an international level has been between 70 and 87 ml/kg/min in men, and between 60 and 78.7 ml/kg/min in women, respectively. Due to lack of air resistance, laboratory testing of RE and vAT are recommended to be conducted on treadmill with 1% slope. %VO2max are in most studies expressed as the average fractional utilization of VO2max at vAT. Much of the current understanding regarding the response to exercise is based on studies of untrained and moderately trained individuals. To use this knowledge to give training recommendations to elite runners is hardly valid. Researchers should the...
Running economy during a simulated 60-km trial
International journal of sports physiology and performance, 2014
The effect of a prolonged running trial on the energy cost of running (C r ) during a 60-km ultramarathon simulation at the pace of a 100-km competition was investigated in 13 men (40.8 ± 5.6 y, 70.7 ± 5.5 kg, 177.5 ± 4.5 cm) and 5 women (40.4 ± 2.3 y, 53.7 ± 4.4 kg, 162.4 ± 4.8 cm) who participated in a 60-km trial consisting of 3 consecutive 20-km laps. Oxygen uptake (VO 2 ) at steady state was determined at constant speed before the test and at the end of each lap; stride length (SL) and frequency and contact time were measured at the same time points; serum creatine kinase (S-CPK) was measured before and at the end of the test. C r in J · kg -1 · m -1 , as calculated from VO 2ss and respiratory-exchange ratio, did not increase with distance. SL significantly decreased with distance. The net increase in S-CPK was linearly related with the percentage increase of C r observed during the trial. It is concluded that, in spite of increased S-CPK, this effort was not able to elicit any peripheral or central fatigue or biomechanical adaptation leading to any modification of C r .