Critical concepts in reducing running related injuries. Part 2

Introduction

In this final post exploring critical concepts of reducing running-related injuries we discuss muscle preparation and running form. Before continuing, you may benefit from reading previous posts ‘basic concepts in running & foot strike patterns’ and ‘running workload and body weight’ to gain a deeper understanding of the mechanics of running whilst also appreciating the relative risk of getting a running-related injury.

The body is subject to 3-4 times your bodyweight during the stance phase of running. The foot/ankle, knee muscles and tendons are responsible for managing up to 75% of this force (1). Moreover, the average runner takes approximately 600 steps per kilometre resulting in significant accumulative stress over distance. Therefore, to hear the knee followed by the ankle are the most frequently injured body parts during or because of running is of little surprise (2).

Most runners experience pain in or around the front of the knee, which is usually due to patella tendinopathy, patella femoral pain or ITB friction syndrome. Foot and ankle related pain is commonly attributable to plantar fasciitis, Achilles tendinopathy and bone stress injuries. The precise reasons for injury development are multi factorial but unquestionably inadequate muscle function and running form can contribute towards the onset of running related injuries.

Therefore, in this post I discuss muscle preparation and consider running form as further methods of reducing the risk of developing a running related injury. In my opinion, running workload and body weight are greater priorities to manage than muscle preparation and running form, especially in the novice runner, as seen in the pyramid of importance Fig 1. However, once these have been addressed muscle preparation and running form may be the key to improving your running performance and reducing injury risk further.

Fig 1.

Muscle preparation and maintenance

Exercise interventions generally reduce the risk of injury in a number of different groups (3,4,5). This is due to preparing and maintaining the body for the sport or activity in question. The success of an exercise intervention is based on two important factors, exercise selection and compliance.

Exercise selection is dependent on goals, which may be either specific tissue stress leading to structural adaptation, optimising movements that are similar to the task or somewhere in-between Fig 2. Positive response to exercise is dependent on compliance as it can take weeks and months to see a genuine reduction in injury risk depending on your current fitness levels.

Fig 2.

It is important to focus our exercise selection on the calf, quadriceps and gluteal regions based on the important role these muscles play during the stance phase of running. The following exercises blend specific tissue stress and optimisation of movement by replicating where possible the role of the muscle during the task of running Fig 3. To help you stay compliant I have chosen just three exercises

Fig 3.

1. Single leg calf rise

The calf complex is responsible for absorbing and generating up to 50% of the ground reaction force during running. It works as an energy generator shortening throughout the stance phase of running and works with the Achilles tendon to amplify force. The single leg calf rise Fig 4 is an adequate stimulus to prepare and maintain this and other important muscles around the foot and ankle.

Fig 4. Move between start and finish positions repeatedly.

2. Single-leg squat

The quadriceps act as an energy conserver working statically, resulting in a spring like exchange between the body and knee tendon promoting energy conservation. Strictly speaking, the single leg squat Fig 5 does not quite replicate this action however, for the beginner to immediate level runner it provides an adequate stimulus to the quadriceps whilst also been a great exercise for single leg/pelvic stability and efficiency (6).

Fig 5. Move between start and finish positions repeatedly.

3. Star plank

Excessive hip adduction and deficits in lateral hip strength are common findings in injury-laden runners (7). The lateral hip muscles in particular the upper fibres of gluteus maximus, gluteus medius and minimus are important to regulate and control this movement and provide pelvic stability. Furthermore, deficits in the abdominal core muscles supporting the pelvis and trunk have been linked to lower limb injury (8). We want these muscles to be working as energy conservers and the star plank Fig 6 is an excellent exercise to isolate and train them for this (9).

Fig 6. Move between the start and finish positions repeatedly.

So how many of these exercises should you be doing? It would be easy to quote some generic figures, however, in the interest of individuality you can calculate this yourself. First, perform the maximum number of repetitions for each exercise on each side and determine your level based on table 1.

Table 1. nb. values predominantly based on practice-based evidence.

Secondly, based on the maximum repetitions performed calculate your training dose. To do this calculate 70% of your repetition max for each exercise and then perform this number of repetitions over 3-4 sets, 3-4 times per week, Table 2 provides an example. You may then retest yourself after 3-4 weeks and repeat the process until you repetition maximum is within the benchmark or very good categories.

Table 2.

In my experience runners who are in the needs work category are at heightened risk of developing a running related injury. Furthermore, numerous studies have shown a link between suboptimal muscle function and injury risk (10, 11, 12). Therefore for the high risk or injury laden runner I would recommend training until you are in the benchmark categories before commencing or increasing running workloads.

Once in the benchmark categories and running regularly, performing a maintenance dose of these exercises is likely to be sufficient to maintain and activate these muscles and movements. Table 3 provides guidance on how to approach this.

Table 3.

Running form

Little consideration is given to how we run after donning our trainers. We simply put them on and go. This is part of the beauty of running, the majority of us are capable with little cost or training required. However, similar to swinging a golf club, hitting a backhand during tennis or striking a free kick in football some are better than others. Therefore, observing individuals who are consistent with successful outcomes and learning common themes may improve our own results.

Running consistently, pain free and achieving our performance goals, which may be to run quicker and or further is a successful outcome. Transitioning to a fore foot strike pattern was long believed to help individuals achieve this outcome through optimising running form (13). However, as discussed in my previous post this is a half-truth which over simplifies the matter.

Observing high-performance runners and discussing form with running coaches, four key elements appear to be of importance:

1. Not over striding. Aim for a high knee as you swing your leg forward, you should then land with a vertical lower leg and your foot below the knee and thus the foot is not too far in front of the hips.

2. Step rate. This usually increases with speed, however, experienced runners tend to take between 170-180 steps per min regardless of how fast they are running. Keeping a higher step rate prevents over striding and experienced runners maintain this step rate by increasing ‘air/flight time’ as they increase their running speed.

3. Forward lean. Lean forward slightly but not too much at the waist. If you lean, too far forward this will require more energy to prevent your upper body and trunk toppling forward whilst encourages over striding.

4. Land softly and quietly with near horizontal feet. If you intentionally run with a view of landing softly, gently and quietly you are more likely to land with a horizontal foot at initial contact. Typically, the braking impulses are lower and shorter in this position.

It is important to remember two significant points when considering changing running form. Firstly, it is energetically demanding to change running form and the majority of runners will revert to their habitual style under fatigue (14). Secondly, the calf and Achilles complex is likely to absorb and generate higher forces during the running form discussed above. This presents a risk of developing a running related injury. Therefore proactive muscle preparation and careful consideration of running workload is required.

I hope you have found some value in the last three running posts. Should you having any difficulty understanding these concepts, planning your running workload or executing exercise preparation please get in touch and I’ll be happy to send further information or support you.