Tuesday, 9 March 2010

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400 Meter Training: Greater Strength = Faster Times (Part 2)

Posted: 08 Mar 2010 09:00 AM PST

This article is guest blogged by Jim Hiserman, author of the books Program Design Method for Sprints & Hurdle Training and Strength and Power for Maximum Speed

GREATER STRENGTH = FASTER TIMES (Part 2)

Part 1 can be found here.

In order for the planning of successful training programs aimed at improvement in the 400 meters, coaches must not only know the compromises in sprint mechanics between the short and long sprint due to the fatigue factor, but also the training methods that best develop the mechanical efficiency required of the longer sprint.

In The Mechanics of Sprinting and Hurdling (Dr. Ralph Mann, Ph.D., 2007), Dr. Mann points to the fact that horizontal foot speed at touchdown may be even more critical for the 400 meters than the 100 meter sprint. In the 100 meters, greater horizontal foot speed at touchdown results in a faster speed and race time.

For the 400 sprinter, faster horizontal foot speed at touchdown also equates to greater velocity but, just as important, in greater overall economy. This helps delay the onset of fatigue and allows for the athlete to cover the initial parts of the race faster AND delay the onset of fatigue until further into the race.

Dr. Mann points to the fact that, through decreasing the braking forces during each touchdown, the 400 runner diminishes the fatigue-producing, pounding impact while also cutting down on the effort required to regain the forward velocity lost during touchdown. It is also important to emphasize greater horizontal foot speed at touchdown because this "sets up" the 400 runner with a shorter horizontal foot distance from the body's center during the early portions of the race.

The horizontal foot distance at touchdown is one of the compromises in mechanics between the short and long sprints. 400 runners contact the ground around 20% farther in front of the body's center of mass compared to 100 runners. This allows for the 400 runners to produce greater vertical velocity, which is not only critical to performance, but also more energy efficient.

Since the change in horizontal foot distance for long sprinters during fatigue is about the same for all sprinters from the non-fatigue portion to the fatigue portion of the race, establishment of a shorter horizontal foot distance during the early, non-fatigue portion of the race will result in a corresponding shorter horizontal foot distance (decrease in braking forces) when fatigued.

Fatigue, during the late stages of the 400, will result in forcing the sprinter to increase the horizontal foot distance and rely on Explosive Strength Endurance to try and maintain the vertical velocity that is lost due to the braking effects of the foot landing further in front of the body's center. It must be pointed out that this requires greater levels of Explosive Strength Endurance during the later stages of the 400 when fatigue is greatest.

Another compromise in mechanics forced by the fatigue that results in the 400 is the leg extension at takeoff during fatigue. Comparing extension at takeoff in the non-fatigued state with the fatigued state showed about 8 degrees more extension in the fatigued state according to Mann's analysis (The Mechanics of Sprinting and Hurdling, page 107). This increase in ground contact time, which decreases stride rate, is a compromise necessary to improve efficiency of the overall performance. Again, this places a premium on Explosive Strength Endurance to counteract the loss of horizontal velocity.

Mann's section summary of the Critical Performance Factors for the Long Sprint echo the results of Speed Strength Endurance and 400 Meter Performance (Paixao-Miguel, P. and Machado-Reis, V., NSA by IAAF, Vol. 19, #4, 2004).

Critical factors that determine successful performance at 400 meters include: 1) capacity to apply large amounts of explosive strength in a properly timed manner, 2) ability to compromise the ground contact times and horizontal foot distances in order to be more efficient, 3) apply the high levels of explosive strength in a manner that elicits an optimal performance through application of a high stride rate and medium stride length.

As mentioned at the beginning of this article, proper training for 400 meters requires the teaching of proper sprint mechanics (in this case the compromised sprint mechanics required by 400 meter sprinting) along with Energy System and Strength and Power Training Plans that include a frequent and relevant testing protocol to insure that timely adjustments to training are made.

Part 3 to be continued…

About the Author

Jim Hiserman is the author of the books Program Design Method for Sprints & Hurdle Training and Strength and Power for Maximum Speed.  Other published articles on this site include:

  1. A Total Sprint-Training Program for Maximum Strength & Power, Core Strength, and Maximum Sprint Speed.
  2. A Sprint & Hurdles Program Design Overview
  3. Training for Development of Maximum Speed
  4. Basic and Advanced Technical Models, including Proper Execution of Key Drills
  5. Speed throughout the Training Year

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