Interval training will help you get the most out of your swim workouts!

Many people go to the pool and swim mindlessly back and forth for 20, 30 or even 60 minutes. Some find this as a meditative escape, and that’s fine, but if you’re serious about stepping up your swimming game and making improvements in stroke technique, efficiency, and endurance you must incorporate some element of interval training into your routine!

What is Interval Training?

It’s not as complicated as you might think. Interval training is simply alternating hard activity with repetitions of either rest or lighter activity. In the gym this is the equivalent of doing 10 repetitions of bench press, then taking thirty seconds rest and then doing another 10 repetitions. If you were to repeat this process a few more times, you’d have a set that looks something like this:

4 x 10 Bench Press @ :30 seconds rest

In swimming, this is no different. Just swap out the repetitions with the distance you’re swimming. For example, if you were to do 50 meters of Freestyle, then take: 30 seconds rest, and then do it again, then your set might look something like this:

4 x 50m Freestyle @ :30 seconds rest

Swimming without interval training is like going to the gym and doing the same exercise continuously without breaks. If you’re running this is fine. In swimming, you’re doing yourself a disservice. Here are some of the benefits of interval training:

Benefits of Interval Training

Whether you’re a novice exerciser or you’ve been exercising for years, interval training can help you jazz up your workout routine. Consider the benefits:

  • You’ll Improve Technique: By taking repetitive but short breaks, you will train your body to only swim at a higher body position and at greater speed.
  • You’ll Burn More Calories: Taking short breaks in the workout allows you train at a higher intensity and thus elevate your heart rate.
  • Improved Aerobic Capacity: As your cardiovascular fitness improves, you’ll be able to train longer, faster and with more efficiency.
  • Added Variety: Swimming the same routine over and over can get boring and monotonous. When you do interval training, there is no limit to what you can accomplish.
  • No Equipment Needed: All you need is a pace clock at the pool or on your wrist. Even if you don’t have a clock, you can do interval training by breath count between repetitions.

How Does Interval Training Work?

Traditionally, the rest interval follows the following equation:

Interval = Swim Time + Rest Time

For example, it you’re doing a set of 4 x 100s @ 2:00 and it takes you 1:30 to complete a single 100m repetition, then you’d have 30 seconds of rest. That entire set will take 8 Minutes ( 4 x 2 Minutes).

The goal of interval training is to be consistent, which is why using a set time as an interval is more beneficial for aerobic conditioning than doing it based on how much rest you want to get after each swim.

Related: How To Swim 10% Faster with MySwimPro Coach

Workout Example

The following workout example comes from our Workout of the Week: Freestyle Fundamentals. It’s a 1,500 yard session that takes about 35 minutes. Each set is on an interval that corresponds to the focus of the set.

For example, if you look at that workout’s Main Set:

  • 6 x 50s Freestyle @ 1:00
  • 1 x 200 Freestyle @ 4:00

The first part (6 x 50s Freestyle @ 1:00) will take six Minutes (6 x 1 Minute/Repetition). If you swim the 50 in 50 seconds, you’ll have the remaining 10 seconds as rest time. These intervals are calculated based on the energy zones of the set, which you can read more about here.

As you improve your aerobic capacity and swimming technique, you’ll be able to swim at a faster interval. For example, soon you may be able to swim 50s at the :55 second instead of 1:00. The more conditioned you are, the more repetitions you’ll be able to at a specific rest interval without exhausting yourself.

Not only will your fitness improve, but so to will your swimming mechanics, stroke efficiency and enjoyment of the sport!

In the MySwimPro app, all of your intervals are tailored to your speed and goals so every workout is unique to you. Learn how it works:

You can continue doing the same workout routine over and over hoping to swim faster, or you can swim with MySwimPro Coach and follow a structured Training Plan that is 100% specific to you with personalized Workouts, technical instruction and support every step of the way.

And it all costs less than your pool membership! 

If this sounds like the program you’ve been looking for to swim faster, improve your technique, and take your swimming to the next level, download the MySwimPro app and get started! Use code SWIM35 to save $35 on your first year of MySwimPro Coach.

Have any questions? Feel free to shoot me an email at



  1. Noon Hashim Hago Ibrahim on

    I am a beginner adult swimmer. So far, I have taken 10 private classes where I learned free style. However, I am still not confident with my arm strokes, breathing and technique. I also want to learn breast stroke. Should I first master my free style / crawl, before I start learning the breast stoke?

    • Taylor Holmes on

      Sounds like you’re putting in the work to improve! It’s ultimately up to you. It can be nice to mix up your strokes and work on technique for both freestyle and breaststroke in the same workout. It can be nice to do a series of focused workouts on one stroke!

  2. I’m 55, 225lbs, 30% body fat losing nicely with swimming and crossover training. Started 90 days ago at 255. Just started SwHIT
    I’m doing SwHIT 3 days a week every other day and have been doing this for 2 weeks now:
    Warm up 4×100 Free
    HIT 10×50 Free (max effort)
    Cool Down 3×100 Mix
    My question …
    I maintain a 0:50 time on each 50 and rest 1 min in between. I take a 2-3 min rest after 5 reps (tread water). Finish the last 5 with a 1:15 rest.
    The reason I rest as long as I do is it feels like I’m completely out of breath, breathing as hard and heavy as I can imagine – seems like a max VO2 moment – heart rate reaches 145-150 after each 50. HR drops to 100-110 on the minute rest.
    I can’t imagine resting only 00:30 or I would have to decrease the intensity I imagine.

    • Taylor Holmes on

      Hi there! For high intensity training like you’re doing, it’s a good idea to give yourself plenty of rest so that you’re able to give your max effort on each rep. Less rest will change the function of the set to more of an endurance or pace type workout, which is totally fine, but isn’t a true high intensity sprint training session.

  3. yes i have been swimming for 10 years now when you get the hang of front crawl you can change every now and then so its more intresting this will boost your confidence and let you break up your front stroke training

  4. Why do interval training or sprints when training for half or full irons? Pick a distance between 1 and 2.4 miles and swim it non stop at differing intensities based on your rest status. Seems weird to me that stopping every 100, 200 yards etc would be enticing when the actual event gives no stops. Can anyone answer this?

    • Taylor Holmes on

      Hi Ben,

      Practicing full distance workouts is great, but you may find that your technique starts to deteriorate over time if you aren’t an experienced swimmer, and that can slow you down. Breaking up your workouts allows you to practice holding your race pace while maintaining good technique. Plus, some people find it easier to get through a longer workout when it’s broken up into different sets.

      When training for an Ironman, would you run a full marathon every time you go out for a run? Or do the full 112 mile bike? No! You work up to the distance and focus on improving your pacing, speed and endurance over time. Swim training should take a similar approach.

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