How Your Movement Changes on the Trail and How Hypershell X Adapts

Take on a steep enough trail and you will probably notice your steps getting shorter as you climb. Once you start heading downhill, your pace and the way you place each step change again. After a few hours with a bag on your back, you may even find that you are walking differently from when you first set out.

There is a lot happening in your body as you make these adjustments, from changes in how your joints and muscles work to the effects of fatigue over a longer route. At Hypershell, we pay close attention to these changes because they help us understand how an exoskeleton can support you across different parts of a hike.

Hypershell X responds to these changes as you move, adjusting its assistance as your pace, stride, and the demands of the trail shift along the way. Let’s take a closer look at why your hiking form changes and how Hypershell X keeps up.

Why Your Hiking Form Changes

Walking involves constant coordination between your hips, knees, ankles, muscles, and nervous system. On a hiking trail, that coordination has to adjust as the gradient and surface beneath your feet change.

Research published in PLOS ONE examined how lower-body mechanics change across different uphill and downhill gradients. The researchers found that the contribution of individual joints shifts according to the slope. During uphill walking, the hip contributed a greater proportion of the positive mechanical power required by the lower limbs, while downhill walking shifted a greater proportion of negative mechanical power toward the knee.

For hikers, these changes happen naturally as you move through different sections of a trail. The way your legs work together during a climb differs from the way they manage a descent, and your stride and pace can change along with those demands.

What Happens to Your Form on a Climb?

Once the trail starts climbing, your body has to generate the power needed to move upward against gravity. As the incline becomes steeper, you may shorten your steps, slow your pace, and adjust your posture while your lower-body muscles work to keep you moving.

A 2024 Journal of Biomechanics study examined walking on level, uphill, and downhill surfaces while carrying different loads. Researchers found that uphill walking increased the work performed by several important hip muscles, while carrying additional weight also increased muscular demands. These findings are especially relevant to hiking, where the physical demands of a climb can be combined with the weight of the gear you are carrying.

This changing movement is something we consider closely at Hypershell. Assistance during a climb needs to respond to the way you are actually moving, including changes in pace and stride as the gradient increases.

Your Form Changes Again on the Way Down

Heading downhill changes the demands on your legs. Your muscles have to control your movement as gravity takes you downward, and the distribution of mechanical power through the lower body changes along with the direction of travel.

The same PLOS ONE study found that downhill walking shifted a greater proportion of negative lower-limb mechanical power toward the knee. On the trail, you may notice yourself shortening your steps, slowing down, or placing your feet more deliberately as a descent becomes steeper or more technical.

For us, the differences between climbing and descending are an important part of designing assistance for hiking. The support provided on the way up needs to adapt as you reach the top and begin moving downhill, where your body is managing a different set of demands.

Fatigue Can Change the Way You Walk

Your movement can also change as the hike progresses. After several hours on your feet, fatigue can affect how your body performs the same walking movement you were doing earlier in the day.

A 2023 study published in the Journal of Biomechanics examined walking before and after lower-body motor fatigue. Researchers found that participants used more energy to walk at the same speed after fatigue and showed changes in the mechanical work performed by different lower-limb joints. This suggests that fatigue can influence both the mechanics and energy demands of walking.

On a long hike, your stride near the end of the route may therefore look and feel different from your stride at the trailhead. Changes in pace and movement can become part of how your body manages the distance, particularly when the route includes repeated climbs and descents.

Your Backpack Adds Another Variable

What you carry also influences the demands placed on your body. A backpack adds weight that has to move with you on every step, and combining that load with a steep incline can increase the work required from your lower-body muscles.

The 2024 study on loaded walking found that carrying additional weight increased the work performed by several hip muscles, with particularly high demands when heavy loads were combined with uphill walking. The study used loads equivalent to 40% of participants' body weight, which is considerably heavier than what many recreational hikers carry, but the findings help demonstrate how load and gradient can work together to influence walking mechanics.

For an adaptive exoskeleton, these variables matter because outdoor movement is constantly changing. Gradient, pace, fatigue, and the weight you carry can all shape the way you move at different points along the route.

Why We Focus on Adaptive Assistance

A hiking trail can take you through several different movement patterns within a short distance. You might be walking comfortably across relatively flat ground before slowing down for a rocky section, transitioning into a steep climb, stopping briefly, and eventually beginning a long descent.

Research into lower-limb exoskeletons has increasingly examined these changes in human movement. The researchers behind the PLOS ONE study specifically investigated uphill and downhill biomechanics to help guide the development of exoskeletons for varied locomotion. Their findings show how the contribution of the hip, knee, and ankle changes with gradient, highlighting the importance of adapting assistance as movement conditions change.

At Hypershell, we want the exoskeleton to respond to the person wearing it as they move through the environment, keeping assistance aligned with changes in gait and pace throughout the journey.

How HyperIntuition Responds to Your Movement

The New Hypershell X Series uses our HyperIntuition motion algorithm to continuously interpret your movement and adjust assistance in real time. Working together with HyperSense, the system processes movement data to recognize changes in your gait and respond as you accelerate, slow down, stop, start, or move across changing terrain.

In TÜV Rheinland testing, the latest HyperIntuition system recorded a response time as low as 0.31 seconds and achieved a 97.5% human-machine synchronization rate across uneven terrain. This responsiveness helps keep assistance closely aligned with your movement as your pace and stride change.

For hiking, that adaptability becomes especially important because the way you move can change repeatedly over the course of a route. HyperIntuition allows Hypershell X to respond to those changes as they happen.

Supporting the Climb and the Descent

The differences between uphill and downhill movement also inform how Hypershell X provides support across changing terrain. As you climb, the exoskeleton provides assistance to support forward and upward movement while your body works against gravity.

When the trail turns downhill, our upgraded Descent Assist provides controlled support as you move through the descent. The New Hypershell X Series can also adapt when your walking speed changes. Low-Speed Enhance provides stronger support at slower speeds, helping the system remain responsive when you naturally reduce your pace on steep or demanding sections of the trail.

Together with HyperIntuition, these features allow the assistance to follow changes in your movement across different stages of a hike. As the gradient, pace, and way you walk change, the system continues to interpret your movement and adjust its support.

Designed for the Way You Actually Hike

Hiking involves constant changes in movement. A comfortable stride across flatter ground can become shorter as the trail climbs, followed by more controlled steps on the way down. The weight you carry and the fatigue that develops over several hours can introduce further changes as the route continues.

Research into walking biomechanics helps us understand these changes in greater detail, and that understanding is important to the way we think about wearable assistance at Hypershell. Outdoor movement is dynamic, and our technology is designed to stay responsive as the demands of the trail evolve.

With HyperIntuition continuously interpreting your movement, the New Hypershell X Series can adapt its assistance as you climb, descend, change pace, and move further along the trail, giving you support that keeps up with the way you hike.

References

Nuckols, R.W., Takahashi, K.Z., Farris, D.J., Mizrachi, S., Riemer, R. and Sawicki, G.S. (2020). Mechanics of walking and running up and downhill: A joint-level perspective to guide design of lower-limb exoskeletons. PLOS ONE, 15(8), e0231996. Available at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0231996

Sturdy, J.T., Rizeq, H.N., Silder, A., Sessoms, P.H. and Silverman, A.K. (2024). Concentric and eccentric hip musculotendon work depends on backpack loads and walking slopes. Journal of Biomechanics, 163, 111942. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0021929024000198

Kao, P.-C., Lomasney, C., Gu, Y., Clark, J.P. and Yanco, H.A. (2023). Effects of induced motor fatigue on walking mechanics and energetics. Journal of Biomechanics, 156, 111688. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0021929023002579