Even Pace Swimming

The more time I spend swimming, reading about swimming, trying stuff out, the more I realise that even paced swimming is incredibly important if you want to go a long way.

Luckily there are a lot of tools available to help with that these days:

(1) Swim watches – count your lengths of the pool and the pace for sets, or even gather stats for every length.  Brilliant at keeping a tally of what you have done in a session, but not necessarily giving you feedback as you go along.  You have to stop to peer at it, to see how many lengths you have done or how fast you have been swimming, which may defy the point.  I have the Poolmate Pro for pool swimming:


and the Garmin Forerunner 910XT for open water GPS.

Garmin Forerunner 910XT

Garmin Forerunner 910XT

(2) Tempo trainer. I bought one of these ages ago, but it didn’t last more than a month or  so  due to some pretty poor waterproofing.  Essentially it is a small widget that fits under your cap or attaches to your goggles, which generates a beep according to whatever you tell it. 

You can either set it to help with stroke rate, timing your strokes to coincide with the regular beeps, or you can set it to help with how long it takes you to swim each length.   Then you aim to hit the wall at the same time as the beep every time.  Fall behind and you know you need to make it up.  Move ahead and you know to ease up a little.

I wish I had (a functioning) one of these right now, as I think I would use it a lot, but I am worried that if I get another one it will have the same poor build quality as the first, and another £30 or so goes down the drain.


Maybe I should give them another chance……

(3) The pool clock.  This is fine for doing interval work.  For instance if you are doing 20 x 100 on 90 seconds, going on 100 seconds, then this works fine, but say you are trying to do mile sets on 98 seconds per 100 m, then it is a slightly harder challenge to keep up with the mental mathematics, and work out every 100 m how you are doing.


Having said that, I did give something like this a go the other morning. 

I woke up on Thursday with a sore nose and throat, having been unable to breathe through my nose all night, and having had a pretty terrible sleep.  I was also feeling achy and ill.  I decided to adopt the ‘kill or cure’ approach and go for a nice challenging swim before work.  I got to the pool around 6.40, and decided to do an even paced 5 x 1 km swim, at 95 s/100 m pace, going every 17 minutes.  I decided to use the pool clock this time, which is something I have never really tried before for some reason.  It has always been a case of stopping the swim watch at the end of a set and being happy/content/disappointed to see what the pace was.

I was surprised how well it went.  The sets obviously got harder as they went on, the first one having to make an effort to not go too fast, through to the final one feeling the pace a little, but still not killing myself by any means.  I ended up with this awesome looking session:

5 x 1 k on 95

Each one of the sets were 15:50 +/- 2 seconds, each calculated at 95 s/100 m, each (apart from the first) at 9 strokes per lengths (actually 9 times turning my left arm over), and at the same stroke rate.  I do always doubt the calorie calculation though.  This suggests I burned 1,840 calories in 1 hour and 24 minutes which seems a little far-fetched.  It would be great to hear people’s comments on that.

Did it kill or cure?  Well neither.  I continued to move slowly downhill, and ended up spending most of the day after (yesterday) asleep in bed.  It has moved to my chest as well now, so probably best to give the pool a miss for another day to allow my lungs to recover.  At the moment there are still billions of (probably) viruses making merry down there; I need to give them the chance to die.

Jesus Green Opens

Today, Jesus Green Lido opened.

The 90-year old lido is a full 100 yards long, because yards are what people dealt with in those days, even in the UK.  It would be easier if it was metres, but there you go (100 yards is 91.44 m).  So 18 lengths of the lido is 1800 yards, or 1645 metres, or about 1 mile and 35 metres.

Now that we have the conversions sorted, let’s talk about what it was like.

Firstly, the fine weather of a week or so ago in the UK has sadly departed. It was about 12 degrees air temperature, and slightly warmer in the water at 13.3 C (56 F), according to the blackboard at the pool entrance, though it felt pretty fresh in the water.

The pool was not busy.  I was glad while getting changed not to be bothering with a wetsuit like I was the previous year.  Last year I was using the pool as the only place locally where I could easily train for the wetsuited Dart 10 K without cooking in an indoor pool.

There were a few hardy skin swimmers, and a few wetsuited people as I started the first 18 length set.  It definitely felt cool, though not unpleasant once the first couple of minutes were out of the way.  First 18 lengths – 27:15 – 1:40/100 m – nice easy pace. 

The second 18 lengths felt lovely.  Still cool, but almost Zen swimming, still all bilateral and very peaceful.  I wasn’t sure at this point whether I would be doing 2 or 3 miles.  I had left myself the option of stopping after 2, but was enjoying the swim, so decided to carry on.  Second 18 lengths – 28:03 – 1:43/100 m – still felt easy, but not that 1:43 easy.  The cold was clearly starting to make itself felt.

After about a minute of rest to have a drink and admire the view, I pushed off for my final 18 lengths, and immediately felt a little odd.  For the first couple of lengths, all of my side muscles on both sides were tight, like I have never felt before.  Everything else felt fine, but that was odd.  I could feel my stroke become a little more ragged.  In the end, my time for the 3rd 18 lengths was 28:35 – 1:45/100 m, and while I was not pushing very hard – it did not feel like my normal 1:45 pace.  Maybe something to do with the 93 m pool length vs my normal 25 m.

I got out and got changed pretty quickly into a warm hat, jeans, 3 layers on top, and crocs.  Bought a Mars bar, and started to shiver.  The shivering carried on for about 15-20 minutes as I drove home in the warm car.  I guess 1:27 in 13.3 C water is about right for the moment for me, though I am sure I could have done another (slightly slower) mile OK.

Towards the end, the pool started getting more busy, as a group of wetsuited triathletes joined.  I was glad to have made my first UK cold water dip of the season.

Are Intervals Working?

Occasionally you get a leap forward in performance, and you go home happy.  This happened today, and coincided with having done a bit of interval training recently.  Maybe this is a coincidence, maybe it’s not.

Monday I did my planned 4 hour swim, aiming for CSS+13 pace, which felt pretty slow in the first couple of hours, but about right for the last couple of hours.  It turned out that the average was about 1:44 per 100 pace, so a second over the target.  But it was good to get my first 4 hour swim under my belt, and I felt just fine afterwards, with only some mild achiness in the shoulders afterwards.  I got 13.2 km done in that time, so an average of 3.3 km/h.  Both my longest swim in duration and distance.

Tuesday I just got a 1.5 km loosener in on a lunchtime.

Then today I decided to have another go at the 3000 m test piece I have blogged about in the past:

W/U – 250 m, 4 x 100 fast, 1900 m straight, 200 m fast, S/D 250 m

Just 48 hours after my longest ever swim, I managed to knock over a minute off the total time for this test set, including the main nautical mile part in 29:20, 1:32.6 per 100 m, 43 seconds faster than ever before.  The whole thing, including rests, took 47.7 minutes for the 3000 m, which I am stoked about.

Only in January I was stoked to take this set under 50 minutes for the first time, so there is some real progress here.

I am a CSS convert!

Intervals II

Two posts in one day!

I unexpectedly got an hour to squeeze in a swim today.  So after writing my CSS/Intervals post earlier, I thought I would have a go at the 20 x 100 @ CSS pace I mentioned earlier.

A few differences from the last time: I was in a virtually deserted pool with a lane to myself; It was the day after a fairly strong 8 km swim and I was a little achy in the shoulders; I had a new pair of Speedo Endurance Jammers on (far better than the last crappy pair of Zoggs which seemed to go all baggy and rubbish after a mere 2 months, acting like a drag suit!).

It was much better this time:


The same 600 m W/U and 400 S/D, but 20 x 100 this time as I had planned.  Also as I had planned I was hitting the CSS target much more closely right from the beginning.  I felt strong, maintaining every other length bilateral right to the end of the set.  At the end I felt pretty worked, but could have carried on.  Brilliant. 

The first time I think I was overestimating how hard CSS pace should feel.  It’s not a sprint, it’s just 10% faster than the usual plodding speed.

Day off now before the (hopefully) 13 km on Monday.


CSS and Interval Training

I have always viewed myself as one-paced in the swimming pool.  I trundle along for miles and miles at around 1:40 per 100 m pace, but aside from the occasional time trial (https://swimsequence.wordpress.com/2013/01/31/january/) I rarely churn the water up unduly.

However, a week ago I decided to finally take the plunge, and dip my toe into the scary waters of interval training.  Before starting any intervals, it is important to understand what your CSS is.  CSS stands for Critical Swim Speed, and is the speed that corresponds closely to your lactate threshold.  It is this speed that you are supposed to try and maintain during a CSS interval session.

You get chapter and verse on CSS if you go to the SwimSmooth website:


There are detailed instructions on there about how to measure your CSS, but essentially you do the following:

(1) Warm up – I did 24 lengths at my usual trundling speed – about 1:40/100 m

(2) Rest for a couple of minutes

(4) 400 m as fast as you can – 5:43 – About 1:26/100 m pace

(5) Rest for a couple of minutes

(6) 200 m as fast as you can – 2:44 – About 1:22/100 m pace

(7) 16 lengths Warm Down


You then take the timings for the 400 and the 200, and put them in to a formula on the Swimsmooth website, or on their free Swimulator App.  This spits out your CSS speed, in my case 1:30/100 m.


The day after measuring my CSS, I did my first interval session, starting off nice and easy with the following set:

600 m W/U Easy

10 x 100 @ CSS pace, on 1:40

400 m W/D Easy

This is what the pace for this set came out as:







Whoa there!

Looks like I have a very poor idea of what swimming at my CSS actually feels like, as I was going way too fast, especially at the beginning.  There’s actually quite a big difference between 90 and 86 (well, 1 second a length, obviously), and you are not really supposed to be swimming below your CSS.  This is probably the reason I felt pretty tired.  I was working pretty hard.

Next time I do this I will try and dial in the pace to closer to to 90s, and not beat myself up too much if I go a second or two over once or twice.  I will also be aiming to take the number of reps out to 20.

It is also important to understand the pace you are going to swim at for longer sessions.  I have the following approximate paces at the moment:

(1) Hard 5 K session – average of CSS + 5 seconds

(2) Hard 10 K session – average of CSS + 9 seconds

(3) Easy 10 K session – average of CSS + 11 seconds

I have rarely swum much past 10 K in the pool.  It just gets too boring and time consuming.  But it is something I am planning on doing soon, hopefully starting with a 4 hour session on Monday (it’s a public holiday in the UK).

I will probably try and dial in at CSS + 13 seconds for a 13 K or so swim.

What might my pace be in the channel?  Well I guess it all depends.  So far my open water swim speed seems quite similar to my pool speed, but in the open water so many more variables are in play, the temperature, the waves, the wind, current to name just a few.  I have seen people suggest that your CSS speed + 20 seconds might be about right for the 35 km or so of the channel, but is that fast enough to stop you getting cold.

I guess I have the next year and a bit to find out more about how this plays out.  Jesus Green Lido opens soon, and it will be great to get into some cold water…….