Training paces in this lab come from Jack Daniels’ VDOT system. A recent race distance and time estimate VDOT, an index of current endurance fitness. That value is converted to Easy (E), Marathon (M), Threshold (T), Interval (I), and Repetition (R) paces.
Volume tools answer arithmetic questions about weekly, monthly, and annual distance. The 10% rule and 80/20 split are popular heuristics you apply to numbers you already trust. Long-run percentage and run frequency connect session length to the week.
The paces and volume figures are training estimates, not prescriptions. They do not replace coaching, and they do not know your injury history, terrain, or recovery. Cite: Daniels’ Running Formula. Details and limits are on the methodology page.