Acceleration and Deceleration.

In almost all sports whilst top end speed is important, acceleration is the key factor in attack and defence.  If we think of Messi, Maradona and Pele in Football or in Rugby of Bennet, Williams, Robinson or Colby it is easy to see what that burst of pace does. Equally in defence, unfortunately for the brilliant defenders, the attacks always make the highlights. 

If you  look closely, you will see that half the trick is the ability to STOP suddenly, change direction and go again.

To stop suddenly, to decelerate or slow down quickly, is often an overlooked skill though it is a critical component of success on the field. Effective deceleration involves generating significant braking forces in a short period, which places immense mechanical forces, as much as 6* bodyweight on the MTU(Muscle Tendon Unit) of the leg. If the legs aren’t  strong deceleration may cause injuries/ruptures  to Achilles Tendons, the ACL/MCL complex ruptures or strain/tear muscles. As such, athletes should train specifically to improve their braking ability to avoid injuries and perform at their peak.

This article explores the demands of deceleration, the physical requirements needed to master it, and how Desmotec Flywheel Eccentric Training devices can help in enhancing an athlete’s braking capabilities and reduce the risk of injury

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Deceleration Ability-Physical Requirements and Solutions.

In his thesis-Neuromuscular determinants of horizontal deceleration ability in team sports…. (https://humanbrakingperformance.com/research), Dr.Damien Harper

sought to not only investigate what was required to decelerate but also assess the ability to decelerate. After analysis of matches it was discovered  that there were more frequent high intensity decelerations in a game than accelerations. He used radar technology to identify a number of kinematic and kinetic variables that could detect moderate changes in maximal deceleration. The acceleration-Deceleration Ability test (ADA) was used to examine associations with isokinetic eccentric and concentric knee strength capacities and countermovement and drop jump kinetic and kinematic variables

It can been seen from the results that there was a very clear correlation between Eccentric KF and KE strength at 60° and deceleration times.

This backs up studies on COD(Change of Direction)  which showed a clear consensus that higher lower limb eccentric strength facilitates superior braking capacity(P.A.Jones et al-2009,2017,Lockie,Shultz et al 2012,Spiteri,Nimphius et al 2014

Taken together all these studies demonstrate the importance of unilateral eccentric KE strength in promoting deceleration ability.

Braking Exercises

The aim of all these resistance exercises is to increase the ability to attenuate shock throughout the lower limbs, especially the ankle and knee , since ground impact forces are substantial -upto 6* bodyweight.

Eccentric maximal strength and this Eccentric strength training has been identified as an important factor in high braking force tolerance. The Eccentric training will strengthen and stiffen the MTU(Muscle Tendon Unit).

There are various methods of improving Eccentric strength from sprinting downhill to using bands however resistance training is generally the most effective.

Eccentric strength is very difficult to increase in traditional resistance training methods as load is determined by Concentric capacity. It is therefore important to find Eccentric Overload (EOL) Exercises. There are some effective traditional methods like slow barbell descents and weight releases (https://rubiconsports.co.uk/desmotec-old/how-does-eccentric-flywheel-training-compare-with-traditional-weight-training/) 

that have been used for many years, but by far and away the most effective way to overload the Eccentric phase is with Flywheels devices such as  Desmotec D and V line.

When using these machines  at least 2 and 3 sets of 6 reps is required to get a meaningful PAP (Post Activation Potentiation)response

(Effects of Postactivation Potentiation after an Eccentric Overload bout on Countermovement Jump and Lower-Limb muscle strength- Marco Beato,Adam Stiff and Giuseppe Coratella)

Summary

The ability to decelerate quickly separates the top players from the also rans. Fast deceleration puts a huge strain on the body and the braking forces can cause injury. Stronger legs will mitigate against the possibility of injury. Whilst absolute strength gained from traditional Concentric Resistance training is essential, it has been found that Eccentric strength is even more vital. Why? Eccentric contractions exploit greater muscular mechanical efficiency, improved motor unit synchronization and selective recruitment of higher-order motor units  in comparison to concentric contractions. 

(Validity and reliability of a flywheel squat test in sport Marco Beato , Adam Fleming , Alexander Coates & Antonio Dello Iacono)

The best Eccentric Overload (EOL) Exercises come from flywheel devices such as 

such as  Desmotec D and V line.

These offer variable resistance from not only the effort of the individual(the more you pull the more it will pull you back) but also through a large range of Inertial Discs.

References:-

1. Neuromuscular determinants of horizontal deceleration ability in team sports…. (https://humanbrakingperformance.com/research), Dr.Damien Harper
2. Effects of Postactivation Potentiation after an Eccentric Overload bout on Countermovement Jump and Lower-Limb muscle strength- Marco Beato,Adam Stiff and Giuseppe Coratella
3. Effect of Volume on Eccentric Overload–Induced Postactivation Potentiation of Jumps Kevin L. de Keijzer, Stuart A. McErlain-Naylor, Antonio Dello Iacono, and Marco Beato
4. The effect of flywheel training on strength and physical capacities in sporting and healthy populations: An umbrella review Kevin L. de KeijzerID1,2, Javier Raya GonzalezID3 , Marco BeatoID1,2*
5. Validity and reliability of a flywheel squat test in sport Marco Beato , Adam Fleming , Alexander Coates & Antonio Dello Iacono

Ready to enhance your braking capabilities and elevate your game? Discover how Desmotec’s Flywheel Resistance Training can transform your performance. Visit our websites today!