Heart Rate Zone Training Intervals

Many consider "interval" to refer to the work period, others the rest period. Regardless, intervals are a common way to train by increasing your heart rate for a given period, with a specific period of rest. For a given amount of training time, intervals are a highly efficient means to achieve a specific training goal. Guidelines for intervals apply to any sport in which the strength and function of the cardio-respiratory system for success is critical, such as cross-country skiing, swimming, cycling, running, and soccer.

Done properly, interval training can increase your anaerobic and aerobic capacity. By repeatedly exposing muscles to a high level of exercise, you improve their resistance to fatigue. This training also teaches your body to recover quickly from different training stresses, and it is in the recovery mode that your body repairs and improves metabolic and musculoskeletal systems.

Make sure you have a good understanding of your heart rate zones, and are using your heart rate monitor while training. Each interval should be done with maximal effort (on an intensity scale of 1-10, they should be at a level 8-9).

These are guidelines for performing intervals to train each of the body’s energy systems. The phase of training you are in will determine which one you should perform.

To develop your ATP-phosphagen system (used in sprints) your work interval should be 10-30 seconds in length, with 30-90 seconds of recovery. Between 10 and 20 work intervals should be performed per workout.

To develop your lactic acid system (used in race surges, bridging gaps and Time Trials), work intervals should be between 30 seconds and 120 seconds, with recovery twice as long as the work interval. Between 6 and 15 work intervals should be performed per workout. These are often done on hills to develop leg power, and are sometimes called "hill repeats."

To develop your aerobic energy system (used often!), work interval should be between two and six minutes, with the recovery the same length of the work interval. Between three and six work intervals should be performed per workout.

NOTE: Before adding intervals to your routine, make sure you have an aerobic base. Generally speaking, this means two months of training in your aerobic zone (65-75% of your maximum heart rate) at least 5 hours per week.

Do not do an interval workout using more than one energy system, and separate interval workouts by at least 36 hours.

The final tip is to have a goal in mind when setting out for each workout. Whether it’s a working recovery ride, hill climbing, or a recovery run, make it count.

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Jonathan Siegel, Director of Coaching
JDS Sportcoaching, LLC

Jonathan Siegel, CSCS, is an RRCA-certified running coach and certified cycling coach. If you have training questions or comments or are interested in a lactate test, contact JDS Sportcoaching,LLC.