Field Event Tips for Physical Education Class: Are Inclined Boards Really Effective in Long Jump Training?

Inclined boards and raised flat boards have long been used in long jump training. These training aids get jumpers higher in the air because they provide an elevated takeoff point.

But are these boards really effective? In fact, a study at the University of Tsukuba in Japan proved that such jumping aids are indeed effective and discussed the reasons why.

The Study
Eight male club-level long jumpers performed jumps under the following conditions:

Using a regular takeoff.
Using a 5 cm high flat board.
Using a 2.5% inclined board.
Using a 5.0% inclined board.

The boards were all .6 meters long and .4 meters wide. They were made of solid plywood with a rubberized surface.

The subjects used a medium distance runup of 14-15 strides. Video and force plate information was recorded for the jumps.

Left: Jumping Off a Raised Flat Board
Middle: Jumping Off a 2.5% Inclined Board
Right: Jumping Off a 5% Inclined Board

Results
The jump distances off all three boards were significantly longer than those recorded under normal conditions.

Through video observation, it was found that the flat board produced different effects than the two inclined boards.

When using the flat board, the body pivoted more quickly over the takeoff foot, and the knee of the takeoff leg was less flexed at contact. These factors produced better height on takeoff.

With the inclined boards, the jumping foot experienced fewer downward forces on contact. Since downward forces must first be overcome before lift can be generated, reducing them allowed for a higher takeoff velocity. This increased velocity was achieved with little change in takeoff motion.

Conclusion
Because the long jump takes place at high speeds, it is difficult to learn the desired movements and timing via full-out practice jumps. That's where these boards can be useful. They allow jumpers to experience the takeoff and in-air phase of the jump at a speed and height that approaches that of a full-out attempt.

Raised flat boards, at a height of 5 cm (about 2"), improve the ability of jumpers to pivot the body over the takeoff foot, which is one of the ways that vertical velocity is generated. It also reduces the flexion of the knee of the takeoff leg. It has been shown that a straighter knee reduces the amount of strength needed to lift the body's weight, which results in greater jumping height.

Incline boards with an inclination of 2.5% to 5.0% increase air-time by reducing downward forces at impact, which increases vertical speed at takeoff.

Reference: Effects of an Inclined Board as a Training Toolon the Take-off Motion of the Long Jump Hiroyuki Koyama, Yuya Muraki & Andmichiyoshi Ae (University of Tsukuba, Japan), Sports Biomechanics, Volume 4, 2005. http://www.twu.edu/biom/isbs/

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