Effects of optimal pacing strategies for 400-, 800-, and 1500-m races on the[Vdot]O₂response

Abstract

The aim of this study was to compare the evolution of oxygen uptake (VO2) in specifically trained runners during running tests based on the 400-, 800-, and 1500-m pacing strategies adopted by elite runners to optimize performance. Final velocity decreased significantly for all three distances, with the slowest velocity in the last 100 m expressed relative to the peak velocity observed in the 400 m (77%), 800 m (88%), and 1500 m (96%). Relative to the previously determined VO2max values, the respective VO 2peak corresponded to 94% (400 m) and 100% (800 and 1500 m). In the last 100 m, a decrease in VO2 was observed in all participants for the 400-m (15.6 ± 6.5%) and 800-m races (9.9 ± 6.3%), whereas a non-systematic decrease (3.6 ± 7.6%) was noted for the 1500 m. The amplitude of this decrease was correlated with the reduction in tidal volume recorded during the last 100 m of each distance (r = 0.85, P < 0.0001) and with maximal blood lactate concentrations after the three races (r = 0.55, P < 0.005). The present data demonstrate that the 800 m is similar to the 400 m in terms of decreases in velocity and VO2.

How to Run 100 Meters

“…In order to mathematically describe a race, one needs to know theV O2 curve. We get information from [11] to construct the curve σ(e). In Figure 3, we have plotted theV O2 curve (that is, σ(e(t))) versus time for a 400m and for an 800m.…”

“…One of the aims of this paper is to bring a mathematical justification and explanation to this phenomenon, and explain why, using coupled ordinary differential equations, the best use of one's resources leads to a run with the last third in deceleration. In fact all distances are not run the same way [11]: for distances up to 400m, the last part of the race is run slowing down, while for distances longer than 1500m, the first part of the race has an initial acceleration, the middle part is run at almost constant velocity, and there is a final acceleration. The 800m is an intermediate race.…”

“…When the race is longer, the dependence of σ on time is well known [11] and varies according to the length of the race: σ, as a function of time, is linear increasing until it reaches the maximal valueσ and then is decreasing to its final value σ f , which corresponds to the rate of aerobic transfer when there is no anaerobic energy left. As a function of energy, we can take the following model, which has the opposite monotony since e(t) decreases from e 0 to 0 with time: where e 0 is the initial value of energy,σ is the maximal value of σ, σ f is the final value of σ at the end of the race, and e crit is the critical energy at which the flow of aerobic energy into the anaerobic container starts to depend on the residual anaerobic energy because of an extra retro control mechanism.…”

How to identify the physiological parameters and run the optimal race

“…In particular, a drop in the rate of oxygen uptakeV O2, at the end of the race, leads to an increase of velocity and propulsive force. The experimental results of [4,5] show that the rate of oxygen uptakeV O2 is not constant throughout the race but, on a 1500 m, rises steadily from an initial value of about 12 ml min −1 kg −1 to its maximum value 66 ml min −1 kg −1 over the first 20 to 40 seconds of the race and then drops to 60 in the last 200 m. Using the Respiratory Exchange Ratio which predicts that 1 L of oxygen in the body produces an energy of 20 kJ, the rate of oxygen uptake available for an effort can be converted into an energetic equivalent per unit of mass. This equivalent depends on the intensity of effort and can vary from 19 to 21, but 20 is a good average value [11].…”

“…The aim is to 4) with the conditions: 5) and solving (1.1)-(1.2)-(1.3). This optimal control problem leads to a race in three parts (for distances bigger than 400 m):…”