An Explanation of Send-Off Intervals
By Kerry O'Brien
Head Coach of Walnut Creek Masters
Intervals and When to Go

A common dilemma among beginner to intermediate swimmers is the concept of Send-Off Intervals. These refer to the total amount of time between repeats in a set. In the interval time, there is the amount of time needed to perform the swim plus whatever time is left is used for rest. The less time used to complete the swim, the more is left for rest before the beginning of the next repeat interval cycle.

As an example, by merely resting :15 sec between your repeats, there is no accountability for the time of the swim. The repeats could be getting progressively slower, but the rest remains the same. There is a time and place for this kind or training, like just trying to build an aerobic base (ex: swim a 1,500 with :15 rest every 300). Here the focus is primarily swimming a lot of laps and building conditioning.

But, as training progresses and you begin to use different energy systems for pacing, speeds and other training and race strategies, the intervals become more exact and beneficial. Another nice advantage to using send-off intervals is that you will virtually always leave on a 5 or a 0, therefore calculating speeds and pace is much easier.

The big deal however is accountability - keeping you true to a plan within the set. Most sets have an underlying reason for doing them. Interval Training will make the biggest difference and offer the largest payback in terms of improvement. Getting comfortable using intervals just takes practice. Start with easy to calculate intervals and progress from there. In no time, your swimming will become more meaningful to you, guaranteed!

See the workout below for examples.

Good Swimming!