Improve your running efficiency
Ahead of this September's ABP Southampton Marathon, Dr Adam Hawkey, Associate Professor of Sport Science and Human Performance at Solent, explains how biomechanics could help improve your running efficiency.
Stride Length/Stride Rate
With participation in marathon running increasing annually and ≤ 90% of those training for a marathon experiencing some form of injury, finding ways to reduce injury risk and improve performance are obviously desirable. There is evidence that a combination of high cadence (stride rate), short stride-length, reduced ground contact-time, and increased flight-time are most effective for improving running efficiency and minimising injury risk. So, if you are looking for ways to improve your performance then consider increasing your cadence (by 5-10 strides per minute) and reducing your stride length to see if this works for you.
Runners are often categorised based on their foot-strike pattern: heel, midfoot, or forefoot. While the majority (~75-90%) of runners employ a heel strike action (a figure that rises to 97-99% in novice runners) it is currently unclear why runners prefer a certain strike pattern. It would appear that factors including running speed, shoe design, surface characteristics, training, and fatigue are all influencing factors. However, given that an individual’s footfall pattern is intrinsic, difficult to alter, and without correct alteration could result in increased injury risk, runners are advised to utilise their current running patterns; only adopt a new strike pattern if advised to do so by an experienced, and qualified, expert.
The position of the body during running can also affect performance and injury risk. The main things to focus on are i) trunk position – while there is conflicting evidence as to whether a forward lean is beneficial for running economy it could help to maintain forward centre of mass movement. If leaning, ensure that the lean is generated from the ankles not the waist. ii) trunk and pelvis balance – controlling this (i.e. avoiding ‘rolling’ at the hips) avoids any undesirable movement, which wastes energy and can increase stress on the lower limbs. iii) hip and knee alignment – controlling any misalignment (i.e. avoiding inward knee movement), especially over long distances, can reduce injury risk.
Hand carrying items
Arm kinematics (motion) in recreational runners is often affected by carrying items in the hands (e.g. water bottle and/or a Smartphone). Most of us carry items in our hands when we are running, but recent research by Solent staff members Thomas Gray and Dr Adam Hawkey suggests that carrying items in the hands can have a negative effect on the kinematics of the lower limbs and subsequently on running economy. It is therefore advisable to avoid carrying items in the hands where possible. Consider options such as a lumber pack/belt or hydration vest for your fluids, and a hip belt or arm strap for your phone.
Given that all contact between the body and the ground during running is through the foot complex, factors relating to footwear are crucial for a marathon. One factor is clearly comfort, and finding a pair of shoes that fit well, offer sufficient cushioning, support, and comfort is therefore of high importance. However, how heavy the shoes are may also be of relevance, as research has shown that the mass of a shoe is also related to performance. A reduction of just 100g in the shoes mass can reduce VO2 (the amount of oxygen we use) by 1%. This may not seem much, but it can correlate to a speed increase of ~0.5%, which over a marathon distance could reduce a runner’s time by ~3 minutes. Therefore, the advice here would be to try and find a comfortable, lightweight, footwear to train and race in.