The Calculator - Explained
The calculator uses 2–3 time trial performances (ranging from 2 to 20 minutes) to estimate critical speed through linear regression analysis. In addition, it can estimate your first threshold based on that critical speed value.
This is currently a prototype and has not yet been scientifically validated. That said, it provides a solid framework and should be reasonably accurate for most athletes. The only definitive ways to establish the first threshold are lactate testing or an assessment of oxygen uptake kinetics - both of which require lab equipment that most athletes don't have access to. This calculator was created by Max Trube to bridge that gap and offer a practical alternative.
The Calculator - Training Zones
All running training plans on this site are built around the 3-zone model. By performing 2-3 all-out time trial runs (ranging from 2 to 20 minutes), this calculator maps out all three of your training zones, giving you a clear structure to build your training around.
The Calculator - Explained
The calculator uses 2–3 time trial performances (ranging from 2 to 20 minutes) to estimate critical speed through linear regression analysis. In addition, it can estimate your first threshold based on that critical speed value.
This is currently a prototype and has not yet been scientifically validated. That said, it provides a solid framework and should be reasonably accurate for most athletes. The only definitive ways to establish the first threshold are lactate testing or an assessment of oxygen uptake kinetics - both of which require lab equipment that most athletes don't have access to. This calculator was created by Max Trube to bridge that gap and offer a practical alternative.
The Calculator - Training Zones
All running training plans on this site are built around the 3-zone model. By performing 2-3 all-out time trial runs (ranging from 2 to 20 minutes), this calculator maps out all three of your training zones, giving you a clear structure to build your training around.
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