Relaxing the shoulders can be difficult. Many people believe their shoulders are relaxed, but they are not. When we walk, our shoulders often tighten and rise above the desired position. This is like adding friction to the axle of a car.
Observe the height of your shoulders and check whether they are relaxed. Since you won’t be carrying a ruler, simply place one hand on your shoulder and lower it as far down as it can go. When your shoulder is all the way down, it is relaxed.
As a last check, while race walking, try lowering your elbows as if trying to drag them along the ground. Did your shoulders lower in the process? If so, use this visualization to help you relax your shoulders.
When out for a long walk, you may experience your arms or shoulders getting fatigued. When this happens, relax your arms, lowering them to your side and shaking them for two or three seconds. Once you get your blood flowing and feel loosened up, continue race walking regularly. This improves circulation, stretches out the muscles and helps you continue walking comfortably.
It’s easy to underestimate how much effort it takes to hold your arm in one position for a couple of hours. When I walk long distances and am not in particularly great shape, my biceps get sore. If your arms constantly feel fatigued, try cross training with some low-weight, high-repetition exercises.