Part 2 How to test aerobic capacity using the PoolMateHR
OK so you swim regularly, you may swim the same sort of session each time or you may have a training plan to follow but how do you know if it’s your technique that’s improving or if you are becoming fitter?
Let’s concentrate on the fitness aspect. Heart rate can be an excellent way to track aerobic fitness levels. A well planned training program can bring decreases of 10 to 20 beats per minute over several weeks of training (Maglischo, Swimming fastest) but we don’t all have access to a personal coach to set a specific regime.
Your aerobic capacity can be tested by undertaking the following session at monthly intervals. Try to make sure each test is completed on the same day of the week, at a similar time, in the same pool, with similar preparations such as diet and sleep etc after an easy day or day off training so you are well rested. Make sure you swim as near as possible at the same level of effort, same stroke type and take the same rest time.
Make sure you are wearing your PoolMateHR heart rate belt and watch.
Press start on the watch,
Swim a good warm up- 400m or so easy, press start to pause
Swim 10 sets of 200m with 20 seconds recovery between each set
(press start when you are ready to swim,
press start to pause after the first 200m, wait until the watch counts to 20 and press start again
swim your next 200 and repeat)
Each 200m should be at a fairly intense but manageable speed. Try to swim each set at the same pace.
After the last 200m, rest for 1 minute- this is important as we need to see your recovery heart rate too
Cool down for a good 5 minutes or longer until your heart rate is at normal levels.
Upload your data to the PoolMatePro software, select the sets data tab in the top right of the screen and you will see your time for the set, it you scroll along to the right you will see your average heart rate for that set.
You need the average heart rate and time for all 10 sets, take the average of all ten average heart rate values and all ten times. Then take a look at your heart rate 45 seconds after the end of the last set and make a note of that too. This will give an idea of how quickly you can recover.
Here are the results of 2 sessions taken one month apart.
| Session | Date | Average time | Average HR in set | Recovery HR |
| 10 x 200m | 01-03-13 | 3:45 | 145 | 114 |
| 10 x 200m | 02-04-13 | 3:42 | 145 | 104 |
The combination of a faster average time and decreased recovery heart rate at the same working heart rate can indicate an increased aerobic fitness.
In the second session it takes 3 seconds less per 200m on average, with the same heart rate, also the recovery heart rate is a lower value. It’s likely that aerobic fitness has increased
Heart rate values can vary from one day to the next naturally so it’s better if you can repeat the test for several sessions to get an idea of the underlying trend.
The recovery heart rate is thought to be a better indicator of fitness than working heart rate and a lower number means you are recovering quicker so are getting fitter. Beware, if your recovery heart rate is higher than the month before this can mean you are overtraining, failing to adapt or coming down with an illness. So take a look at how much training you are doing and how you feel, cut it back if necessary to give your body time to recover.
Getting the most from your PoolMateHR, Part 1
Maximum heart rate when swimming
Heart rates when swimming are usually significantly less than when undertaking other sports on dry land. You may have noticed you feel to be working really hard in the pool but if you measure your heart rate it is much lower than you expect if you are used to monitoring your heart rate when running for example.
This is thought to be a result of several factors, first, the body is in a horizontal position so your heart does not have to work as hard to pump blood around the body against the effects of gravity. Second, the cooling effect of the water reduces body temperature and decreases stress on the circulation. Thirdly, the dive reflex is known to lower heart rate and blood pressure which is a neurological response to immersion in water.
So how does this affect you?
The change between aquatic heart rate levels and dry land levels can be estimated. McArdle et al. 1971, suggested aquatic heart rate was 13% lower than dry land, Sova 1991, suggested a 17 beat per minute deduction was appropriate. Recent research from Brazil (Kruel et al) suggest a comparision test you can undertake easily.
Stand still at the side of the pool for 3 minutes then take your heart rate. Get in the pool and stand in the pool at armpit depth for 3 minutes then take your heart rate again. The aquatic heart rate deduction is determined by subtracting these two values.
If we use the commonly known formula of “220 – your age” to determine maximum heart rate. The maximum heart rate in the pool will be “220 – your age – aquatic deduction”.
e.g. for a 40 year old
Maximum heart rate on dry land = 220 – age = 180 bpm
Heart rate when standing out of pool = 101 bpm
Heart rate when armpit deep in pool = 90 bpm
Aquatic deduction = 101 – 90 = 11 bpm
Maximum heart rate in the pool = 220 – age – aquatic deduction = 220 – 40 – 11 = 169 bpm
Need coaching? we recommend Ray Gibbs
220 Tri Awards 2012
‘Coach of the Year’ (2nd place)
Swim Canary Wharf offer 1:1 sessions, Beginner and Advanced workshops, training camps and video analysis. Based in the centre of the Docklands area in London, they are ideally placed for quick access and transport links from around the UK.


