Real-time biofeedback case – Diminishing a 33% left-to-right difference in dynamic stability

By Philip Cortvriendt – Runeasi expert

During the initial assessment, we observed that the runner’s stability deteriorated over the course of her run. Although she didn’t feel fatigued, a visual inspection revealed that her pelvic stability was compromised. Her pelvis was tilting forward (anteverted position), and her upper body was leaning forward to compensate for insufficient glute engagement.

Notice the increased instability on her left leg

addressing and improving her running form

  • Slowed Down the Speed: We reduced her running speed by 1 km/h. This slight decrease made it easier for her to maintain proper form.
  • Increased Cadence: By slightly increasing her rhythm, we aimed to minimize the prolonged push-off that contributed to her backward pelvic tilt and forward upper body lean.
  • Posture Cue: We added the cue “stay tall” to encourage better gluteal engagement and improve overall posture during the run.
Notice the improvement after cueing

These adjustments led to an improvement of 30% in her dynamic stability, indicating that her stability issues were more related to form rather than fatigue. During the biofeedback session she could maintain the improved stability, which suggests that her previous decline in stability was due to a loss of proper form.


For this runner, the key takeaway is to first master maintaining these improved movement patterns at a slower pace. Once she can consistently maintain good form at lower speeds, she can gradually increase her pace while still adhering to the learned patterns. With the simple cue of “staying tall”, she was engaging her glutes more during the stance phase and ultimately improving her running

Picture of Written by Philip Cortvriendt

Written by Philip Cortvriendt

Philip achieved a master’s degree in physiotherapy & rehabilitation sciences and has core expertise in the field of running, working with both recreational and elite runners. Philip has the unique role of educating Runeasi physiotherapists and helping them translate biomechanical insights into targeted strength and conditioning exercises- specifically on how they can improve their client care using scientifically validated biomechanical insights from our Runeasi analytics.


1. Global movement quality

Track and improve your client’s Runeasi running quality. Identify their weakest link with our advanced visualisation.

2. individual recommendations

Get individual training and cueing recommendations to improve your client’s weakest link.

3. Real-time feedback


4. Session trends

Learn more about your client’s running quality during daily training. Our session trends show when and where the quality drops with fatigue.

5. Quick comparisons

Compare pre-post data to show intervention effects on the movement quality. 


1. No motion artifacts. The Runeasi belt is secured tightly against the body and the skin to capture the actual movements of the body’s center of mass. Attaching or clipping the sensor directly to the pants would allow the sensor to wobble from side to side (i.e., measuring the wobbling of the pants, and not the human body.

2.  Easy to standardize the sensor’s positioning. The Runeasi belt makes it easy to consistently position the sensor close to the center of mass. Attaching the sensor directly to the pants would dramatically affect the reliability of the outputs as the height and tightness of the pants will affect the results. Moreover, these pants attachments often shift sideways while running which further decreases the data quality. 

 3. Comfortable to wear.  Hundreds of runners confirmed that they immediately forget about our belt while running. This allows them to move without any restrictions and allows us to capture movements that are representative of a client’s true biomechanics.



Accurately captures full range of motion and kinetic parameters by leveraging wide sensing range (16 Gs) & high sampling frequency (1000 Hz)


Built to withstand high intensity training and sweating. Suitable for the outdoor elements, come rain or shine. Robust to handle the repetitive and ruthless impact shocks of running.

Lightweight & SLIM

Seamlessly integrates onto the body to support movement without restrictions. Weight: 9.4g/0.33oz with battery. Dimensions (36.6mm/1.44” dia. X 10.6mm/ 0.42” thick)

No charging wireless

Replaceable coin-cell battery with operating time up to months, depending on the usage. Bluetooth® 5.0 radio for effortlessly transmitting data real-time or post-session.