Anyone who has participated in hiking in Colorado knows that it is difficult to trek anywhere without significant elevation change. In our Boulder Physical Therapy and Lafayette Physical Therapy clinics we work with all levels of hikers to both rehabilitate current injuries and keep them on the trails by reducing their risk for future injury. Falling while hiking accounts for the second most common mountaineering injury, and 75% of falls occur during the descent of a hike. It is easy to conclude that these tumbles may occur simply because of muscle fatigue at the end of a long hike. Walking downhill does require repetitive eccentric contraction of the muscles in the lower body as you work against gravity to slow your momentum, and it has been well-studied that fatiguing eccentric exercise (e.g., walking downhill) can lead to changes in proprioception and joint position sense. A recent study published by Werner, et. al., investigated further into this concept to determine whether light-effort downhill walking (e.g., non-fatiguing downhill walking) could still disrupt muscle proprioception and balance.
The study was conducted in two experiments. Measures for both experiments were taken pre- and post-simulated easy downhill walking (walking on a treadmill set at a decline of 20 degrees for 30 minutes). The first experiment measured “leg dexterity” by having participants apply and hold downward pressure on an unstable force plate with one foot. The second experiment measured balance ability in anterior-posterior and medial-lateral directions as well as isometric knee extension strength. Results from both experiments showed that despite participants reporting only a “light effort” with the simulated downhill walking, there was a significant difference in leg dexterity and balance ability in the anterior-posterior direction (with no difference in isometric knee extension strength). The study concluded that even easy downhill walking can disrupt balance and proprioception mechanisms independently of muscle fatigue. Though strength and endurance training remain important components in training for hiking or other dynamic trail activities, safety during downhill walking (even on easy paths around town) may be further improved by incorporating balance and proprioceptive training on unstable surfaces.
At Mend we specialize in keeping our patients active in their preferred level of activity. If injuries or balance impairments are holding you back from the Colorado recreation of your choice schedule your next appointment with the experts at MEND.
Citation:
Werner I, Valero-Cuevas FJ, Federofl P. Mountain Hiking: Prolonged Eccentric Muscle Contraction during Simulated Downhill Walking Perturbs Sensorimotor Control Loops Needed for Safe Dynamic Foot-Ground Interactions. Int J of Environ Res Public Health. 2023; 20(7): 5424. doi:10.3390/ijerph20075424