Stryd will do a great job helping you keep your effort uneven terrain. Stryd can help keep your effort the same in hilly terrain, optimizing performance. While using Stryd on the trail is slightly more complicated, there is no alternative for trail runners that want to improve performance, have accurate pace and distance and track their progress.
1. If you run on trails that are hard-packed with undulations, you can use Stryd as you would on the road. Keep your effort the same on the flat, uphills and downhills. Unless the downhills are gradual (<5% grade), drop your power on steep descents and ignore completely on steep, technical descents.
2. On steep trails, you end up walking. You need to determine a good power hiking target for yourself. The mechanics are very different, your power will be lower while walking (even when moving at the same pace). The power hiking targe cannot be derived from critical power.
3. You will have to determine a good power target yourself for various types of terrain: uphill running, uphill hiking, flat but technical, etc. This is different than for road runners.
4. Check the webinar from Andy DuBois. He is an ultra running coach that uses Stryd with his athletes.
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