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Writer's pictureAnnie Hollest

Threshold Training in Swimming...for Dummies ;-)

If you resonated with my 'One Pace Pony' article a while back, then you need to read this and take action!


Or if you hit the pool with no plan / are still swimming the same speed despite your best efforts, then read on to learn how to increase your endurance swimming speed with a little basic exercise science and proper coaching....


Your Lactate Threshold is the maximum speed your body can sustain at an aerobic intensity, (not balls out, think a 5k run pace, pretty hard, but doable up to a point).


Threshold Training involves swimming at a pace that will improve your lactate threshold speed, which will result in significant speed increases in distance swimming (400m plus). Remember the best distance athletes are not the fastest, they're the ones with the fastest AVERAGE speed.


For most swimmers training using this method involves more swimming at a slightly lower intensity and less rest between sets (15-30 seconds maximum). The secret to improving your lactate threshold (or Critical Swim Speed / CSS pace, they’re the same thing essentially) is to train at this pace, or just below it (i.e. slightly faster).


Here's the steps to smarter distance training.


1. Find your current CSS pace


After a thorough warm up, swim and time 400m at your best effort. Then take a good 5-10 minute rest and then time your best 200m swim.


For example, Jenny swims her best 400m in a time of 7 minutes and 50 seconds. Her 200m time is 3 minutes 50 seconds. There are online calculators available, or in a simple equation is to half the difference between the two times, making her 'CSS pace' per 100m 2:05. This means to improve her threshold she should swim at this pace +/- 2 seconds per 100m.


We then put this time into a Tempo Trainer, a very handy little gadget that sits in your swim hat and beeps at you so you can gauge your swim speed accurately without stopping to look at your watch mid set.


It can be difficult to swim at your threshold pace consistently, many swimmers set off too quickly and then blow up, or don’t swim fast enough. For this reason, you set the Tempo Trainer Pro to beep at certain intervals.


2. Configure the tempo trainer


There are three settings with differ in beep frequency:


  • Mode 3: Stroke Rate mode, more on that in another post soon!

  • In Mode 2 you can set it to beep at larger intervals, such as every 2:05

  • Mode 1 is our preferred interval, beeps in shorter intervals such as every 25m, much easier to pace yourself with!


To use mode 1, you need to work out the time between each beep. This is where it gets a little technical. On a pace of 2:05 every 100m, to beep every time your turn at 25m you set it to beep every 31.25 seconds (the tempo trainer works to two decimal places), since 25m is a quarter of 100m. If you're training in a 20m pool simply divide by 5.


3. Training at CSS pace


An example taster set is the Goldilocks set, which combines 100m with slightly longer distances to help you gauge your ability to sustain this pace:


All freestyle full stroke, with a one beep rest interval (RI).


Get ready to set off on the next beep after you finish the set, i.e. after 31.25 seconds in this example, or your own 25m time interval from your own CSS pace. If you’re really struggling to catch your breath in this period, take an additional beeps rest, but bear in mind that slightly defeats the object of threshold training and you may just need to get used to swimming slightly harder to improve your fitness!


It might feel too easy at the beginning leaving you feeling tempted to put up the pace, but stick with it. See if you feel the same after the 400m at the end and sticking to 1 beep rests!


Baby Bear

1 x 100m RI 1 beep

1 x 200m RI 1 beep


Mummy Bear

2 x 100m RI 1 beep

1 x 300m RI 1 beep


Daddy Bear

3 x 100m RI 1 beep

1 x 400m RI 1 beep


Confused? Come and try our Threshold Training Session every Thursday evening starting on Thursday 3rd March!



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