Reducing Energy Leaks by Improving Trunk Stiffness by Tom Taylor

‘Stiffness’ is a term that seems to be used more frequently in recent years as an important athletic trait, and the term can be used when talking about various areas of the body, such as stiffness at the ankle and at the knee. The importance of ankle stiffness is often discussed in terms of maximising sprint performance, and also other dynamic movements such as hopping and jumping (1,2). One of the reasons for this is that there is greater utilisation of the stored energy during each step, rather than this energy being lost at foot-strike due to low levels of stiffness and therefore higher levels of energy absorption.

A footballer who can utilise greater lower extremity stiffness characteristics will potentially store more elastic energy at landing and generate more concentric force output at push-off; which can positively translate to performance by possibly delaying the onset of fatigue and increasing running speed (3).

Trunk stiffness is also an important athletic trait for our footballers to possess, not only for athletic performance, but also for our players to remain fit and healthy as greater trunk stiffness has been linked to enhanced load bearing ability and spinal stability (4).

During a 90min match, football players will be covering great distances at higher speeds, and completing a large number of high intensity efforts. Being able to complete these actions in the most economical way possible, and reducing excess energy loss where possible can only be a positive thing for the players themselves. One common area in which team sports athletes often leak elastic energy is via excessive trunk movement when running, particularly rotation and lateral flexion of the upper body (5). By stopping unwanted motion via increased trunk stiffness, activation of the abdominal musculature can be viewed as a strategy to enhance stability through generating stiffness and prevent energy loss and enhancing dynamic characteristics of athletic movement (6).

When looking to improve trunk stiffness, there are a number of exercises we can look to include in our training programmes. These will typically begin with some isometric variations, before adding in some external perturbations also which will force us to fight against unwanted upper body rotation and movement.

These exercises can be completed regularly throughout our training week, and are ideal to add in to our pre-training routine in small doses to help ‘switch-on’ our trunk and hip musculature before we head outside on to the pitch.

Lateral Holds

This exercise can also be done by lying on the end of a bench, and having a team mate place their weight on your hips.

Start with short holds, such as 15-20 secs, until you feel comfortable enough to keep increasing the length of each rep (anything near 40secs is tough!).

It’s important that you don’t allow your trunk to start falling, as soon as you can feel this happening, stop the rep and flip over on to the other side.

Lateral Rebounds

In the same start position as the lateral holds, allow your trunk to fall before quickly returning to the starting position. Using reps this time rather than a set time, begin with 8 reps each side before increasing over time to 12 reps.

Lateral Weight Plate Presses

The next progression involves adding in an extra load to the exercise; by pushing the weight plate out ahead of you during the isometric holds, the trunk is having to work harder to maintain that lateral position. Starting with a light weight (2.5kg), aim for 8-12 reps again. It’s important to note that, as with the Lateral Holds, as soon as you are unable to maintain that neutral position, end the set and move on to the other side.

Lateral Rebounds into Plate Presses

The final progression using the Roman Chair incorporates both the Lateral Rebounds and Plate Presses. By increasing the speed of the movement, we are challenging the trunk further to maintain that neutral position. Again, look to complete 8-12 reps at a weight you feel comfortable with.

Suitcase Carries

By carrying an external load in one arm whilst walking, we are creating an uneven frontal plane bending moment. You will need to create enough stiffness through your lateral trunk and hip musculature to prevent unwanted lateral movement towards the loaded side (B. Lee Thesis). Starting with a moderate weight, complete 10-15m at a slow and controlled tempo (maintaining neutral hips and trying not to let your feet cross each other’s path), before dropping the weight, changing sides and walking back to the starting position.

Split Stance Perturbations

The final exercise I’ll mention in this blog post, the Split Stance Perturbations will really challenge the trunk’s ability to rapidly produce enough stiffness to fight against unwanted upper body rotation and flexion. In a shallow split stance position, with arms fully extended at shoulder height, make small and aggressive movements to the left and right. Look at doing 6 left and 6 right movements per set.

For coaches and performance specialists reading this, one method I’ve found to work well when assessing our players’ ability to minimise lost energy via poor trunk stiffness is just simply to watch them run from the front and back when completing linear high speed efforts (filmed efforts are even better). Super simple I know, but excess upper body movement can quickly highlight those players that would benefit from adding in some of the above work into their daily routines. It is just a nice and easy addition to our footballers’ programmes to help minimise any unwanted effects of fatigue as our players train and play regularly throughout the season.


1. Kuitenen, S., Komi, P. V. & Kyrolainen, H. (2002) Knee and ankle joint stiffness in sprint running. Medicine & Science in Sports & Exercise, 34, p166-173.

2. Pruyn, E. C., Watsford, M. & Murphy, A. (2014) The relationship between lower-body stiffness and dynamic performance. Applied Physiology, Nutrition & Metabolism, 39, p1144-1150.

3. Brazier, J., Bishop, C., Simons, C., Antrobus, M., Read, P. J. & Turner, A. n. (2014) Lower extremity stiffness: effects on performance and injury and implications for training. Strength and Conditioning Journal, 36, p103-112.

4. McGill, S. (2007) Low back disorders, 2nd ed., Windsor (ON): Human Kinetics.

5. Joyce, D. & Lewindon, D. (2014) High-performance training for sports, USA, Human Kinetics.

6. Lee, B. (2013) Trainability of core stiffness: studies of core training methods on naive and savvy populations, MSc Thesis, University of Waterloo.