Saturday, 12 March 2016

Moving Posts to New Website!

All my blog posts will now be posted on:

www.dimeperformance.com

Come check out my new posts and keep up to date with new interesting research!

Saturday, 2 January 2016

Squat More To Sprint Faster?

We've all been told that if we want to sprint faster, we need to get stronger and squat more. But is this really the case?

A 2012 study of the 100-meter sprint involved nine physical education students, three national level sprinters and one world class sprinter. Since this review is focused on short sprint speed, only the 4-second distance was measured. The researchers found significant, strong correlations between the index of force application (the direction force is applied), horizontal GRF (ground reaction force in the horizontal direction) and the 4-second distance. However, no significant correlations were found between vertical GRF and 4-second distance. Average and maximal power output were also significantly correlated with 4-second distance.

This was further backed up by a 2014 study. Sprint performances of 10 meters and 40 meters were measured comparing elite rugby league backs and forwards. Backs were found to be significantly faster than forwards in both sprints; however, there were no significant differences in vertical force or sprint mechanics. Significant differences in relative horizontal force and relative power were found between forwards and backs.

Another recent 2015 study looked at elite (international level) and sub-elite (French national level) sprinters over 40 meters. The researchers found the horizontal propulsive force to be significantly correlated with 40-meter sprint performance. In contrast, vertical force was not correlated with sprint acceleration performance. More importantly, there was a tendency towards a negative correlation between vertical force and 40-meter sprint performance.


What does this all mean?

The data suggests that when it comes to short sprint performance, the direction in which force and power are applied (horizontal direction) is more important than the magnitude (how much) of force and power produced overall. Moreover, athletes who can "push" more in the horizontal direction are faster. In addition, producing more vertical force over horizontal force during your sprint (i.e., accelerating with a very upright posture orientating force more vertically while sprinting), may negatively impact your 40-meter sprint performance.

Practical Applications

Here are a few exercises you can implement in your training to develop horizontal capabilities to improve short sprint speed, which is a vital performance attribute in many team and individual sports.
  • Heavy Sled Drag or Prowler Push
  • Heavy 45-Degree Back Extension (specifically 45 degrees as the angle where torque is greatest at the hips better represents the acceleration phase of sprinting than the 90-degree back extension).
  • Kettlebell Swing
  • Glute Bridge and Hip Thrust (all variations)
  • Broad Jump and Broad Jump with Handheld Loading
  • Bounding
  • Medicine Ball Forward Scoop Toss
In this post here, I give examples of contrast pairings you can use in your training to enhance both horizontal force and power capability.

References:


Morin, JB, Bourdin, M, Edouard, P, Peyrot, N, Samozino, P, and Lacour, JR. "Mechanical determinants of 100-m sprint running performance." Eur J Appl Physiol, 112: 3921-3930, 2012.

de Lacey, J, Brughelli, ME, McGuigan, MR, and Hansen, KT. "Strength, Speed and power characterisitics of elite rugby league players." J Strength Cond Res 28(8): 2372-2375, 2014.

Morin, JB, Slawinski, J, Dorel, S, Saez de villareal, E, Couturier, A, Samozino, P, Brughelli, M, and Rabita, G. "Acceleration capability in elite sprinters and ground impulse: Push more, brake less?" J Biomechanics,2015.