Training Zones

Jack Daniels' book about running has a training plan that seems to be highly regarded.

  • LT1 - 75% of maximum heart rate. ~145BPM maybe (for running).
  • LT2 - Average heart rate for a maximum sustained effort for 1 hour.

Zone 1

  • Trains your body to use fat stores as energy.
  • Increases your oxidative capacity.
  • Trains slow-twitch muscle fibres.
  • You can speak a full sentence without taking a breath.

Zone 3

  • Trains your body to use carbohydrates as energy.
  • Trains your glycolytic system.
  • Increases your ability to mitigate lactic acid.
  • Trains fast-twitch muscle fibres.
  • You can barely speak in this zone.


  • Zone 2 is not a good place to train, it's middle of the road and not an efficient use of time or effort.
  • 80% of training should be in zone 1.
  • We have much more energy stored as fat than we do as carbs.