Using unique metrics and world-first data gathered by the INCUS|NOVA we are able to take analysis of one runner’s London Marathon performance to greater depths than ever before.
Zoe has a life-time personal best of 3hr 36 minutes, prior to having two children in quick succession. Her goal for the London Marathon 2021 was 4-hours, which she just missed, finishing in 4hr 20 minutes. Looking at the data gathered by her INCUS|NOVA, (a small wearable device worn in compatible apparel in the centre of the upper back), has been able to offer exclusive insights, not available from other fitness trackers, to see what she can do to hit her goal next time.
“ I had been unsure about whether to run this marathon or defer to next year as I had a hip injury caused by twisting and carrying my child on my right side. I decided to run because I wanted to enjoy London being London again after the quietness of lockdown during the Covid-19 pandemic.”
During her marathon Zoe’s running stride phases were recorded showing stride duration, her flight time and her contact time. Total Stride Time is the Ground Contact Time plus Flight Time. Ground Contact Time is the time between landing and toe-off on the same foot and Flight Time is the time between toe-off and landing on the subsequent step.
Achieving a lower Ground Contact Time and higher Flight Time at a given pace indicates a more efficient running technique. Looking at your Stride Phase values can help pinpoint where in your run your technique changes as you fatigue.
From our data, even without looking at Zoe’s running speed or asking how she felt at each point in her marathon run, we can see where fatigue kicked in. The first half of her run was very consistent with contact time only increasing fractionally toward the mid-way point. After mid-way contact time lengthens and flight time reduces clearly showing her run stride deteriorated and where she opted to run/walk.
“At the beginning I was working on 9-minute miles and was consistent with that until mile 16 when I started to feel my hip injury beginning to hurt. Between mile 16 and mile 20 I chose to run for nine minutes and walk for one. By mile 22 I started to do one minute walking and two minutes running. When I got near the end the cheers of the crowds picked me up and ran the whole of the last mile”.
Take-Off and Landing
The other metric to look at is Take off & Landing, this measures acceleration at the toe off and deceleration at the foot strike phases of your stride. Take Off and Landing changes can indicate when your form begins to degrade as you tire and excessive landing deceleration is one of the biggest causes of running injuries. If you have ever experienced a knee injury running or a calf injury running or even shin-splints watching your take-off and landing data is particularly pertinent.
Landing deceleration is measured as the amount your body slows down when you make contact with the ground, per stride. The closer your deceleration values, illustrated by the red bars, are to 0, the lower your deceleration at impact. Maintaining a landing deceleration of under -0.5g (as Zoe did in the early part of her marathon) shows you are running lightly with good form and little impact. As Zoe’s run continued and she began to tire, her landing deceleration gradually increased to -1.0g.
As higher landing impact is associated with chronic lower-leg injuries such as shin splints, calf-injury or knee-injury, as well as more general muscle soreness, this is something for Zoe to be aware of in her long training runs and events.
Stride Phases is best interpreted when looked at alongside Pace and Take Off & Landing to identify how your run form is affected by certain target paces and when fatigue begins to affect your form.
It’s interesting to note that Zoe’s landing deceleration deteriorated before her contact time in the Stride Phase increased. This suggests that landing deceleration or running impact is something that Zoe should work on in training to avoid injury as it is one of the first indicators of fatigue in her running form and a bad habit she slips into quickly.
“ I was aware that as my hip pain increased I started to land more heavily and lost some control. Looking back I should have paced it better and aimed for ten- minute miles all the way rather than ending up walking.”
How to improve your running stride
Very few runners outside of the elite are able to maintain their technique all the way through an event as long as the marathon, but focusing on technique as well as form during long runs and preparation will not only help Zoe to a faster finishing time it may also protect her against injury.
Changing your stride length running requires focused attention to strength and conditioning as well as run training, but it is time well spent as training to improve your stride will help you to run faster.
Over striding is when your foot lands too far in front of your body. It slows your leg turnover and increases landing forces through your lower body, slowing down your body more than necessary on every step.
Take shorter, quicker steps and watch your upper body movement. A tight upper body can inhibit natural arm drive and throw off your stride. Aim to use your arms to drive through and complement the effort of your legs.
Using INCUS | NOVA run tracker on a technique session will show you how focusing on this coaching tip changes your run.
Lack of control in your calf and ankle during your fore-foot strike phase can result in your foot ‘slapping’ down instead of landing in a controlled way, which minimises impact.
Your calf muscles ( gastrocnemius and soleus) work as an accelerator by providing the ‘spring’ forward and as your brake by slowing and controlling the impact of your forefoot as it hits the ground. Exercises to increase flexibility and develop control and proprioception should be done as part of your training routine. Ideally you would work with a strength and conditioning expert to tailor a series of exercises unique to you, but there are some great examples, such as the simple calf raise, to get you started at Runner’s World.
Using your INCUS|NOVA to monitor your landing deceleration you can see how your conditioning work is helping to reduce your impact, it also allows you to check the balance between your left and right leg. Read how Ironwoman Roz McGinty used her INCUS|NOVA to re-train her running technique to prevent a persistent Achilles injury from reoccurring.
“Seeing my data from the marathon has really helped me to understand why I missed my target time and what I need to improve to reach my goal. Where the INCUS was easy, I completely forgot about it until I took my run vest off at the end.”
“ I could see from my INCUS that my landing deceleration and impact was high and my running form was poor, particularly on my right where I have had physio treatment for a hip injury. Once I recover I’m going to work more with my physio on improving my posture and strengthening my glutes to stabilise my hip. I’ll continue to use my INCUS|NOVA to monitor how the strength and conditioning work changes my technique and really keep an eye on my landing deceleration.”
Don't forget to head to our Run Store and discover how INCUS performance feedback can help you train for your next marathon. The run bundle includes the INCUS|NOVA and INCUS compatible running apparel, everything you need to start improving your running stride.