Your muscles need ATP to contract, but where does it come from? A deep dive into the three energy systems, phosphocreatine, glycolysis, and oxidative phosphorylation, and what they mean for your training.

Dr. Sebastian Reinhard Mar 07, 2026

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From 5K to Ultra: Scaling Your Training by Distance

The principles stay the same but the emphasis shifts as you move from shorter races to longer ones. Here is how training changes across the distance spectrum.

Sarah Karollus Feb 05, 2026