Maximise your indoor training with this simple pool session

Arisa Chattasa 2W Uabuglq Y Unsplash

Purpose of the session

This session has a descending volume theme that I like as psychologically you feel you are making progress. There are several starting points to add or subtract distance. You can also switch from drills to harder efforts if you are feeling good.

How to get the best from it

Many sessions and mainsets are overly complicated. Depending on the events you are undertaking this might be necessary. Without a coach on poolside though to guide you it can make the sets a little tedious and lost in the maths. The most popular mainsets I offer during fitness sessions are challenging, thought provoking, easy to comprehend and allow the swimmer to set their own challenges. Often, allowing the swimmers to dictate effort levels generates more hard work than asking them to meet targets I set. As this series develops you will see more sets like this. I always see it as the best compliment if a session ends and the swimmers are surprised when the sessions seems to have flown by. I hope to recreate this here.


The Every Session – rest = 20secs throughout (25m pool)

Warm Up

  • 500m Front Crawl (FC) every 5th length drill (Also read as 100m FC into 25m drill in a 50m pool.)
  • 400m FC every 4th length fast (75m FC into 25m fast)
  • 300m every 3rd length pull (or all pull in a 50m pool) (Yes the pull buoy will be in the right place in a 25m pool!)
  • 200m swum as 75m FC into 25m kick (choose a kick style that does not necessarily need a kickboard ie FC legs and Breaststroke arms)
  • 100m build pace throughout 1500m

Main set

  • 16x50m FC – 3 swims steady, every 4th 50m fast or drill 800m
  • 12x50m FC every 3rd 50 fast or drill 600m 8x50 every 2nd 50 fast or drill 400m 4x50 all fast or all drill 200m

Cool down

  • 100 easy your choice, swim down 1500m-3.6km

Adapting the session

Very little fitness? After limited swimming last year, perhaps the 1500m extended warmup will be enough. Maybe you only have a 45min slot allocated at your pool. Plenty of time to build and get more done later.

Feeling a little fitter? Perhaps start at the 12x50 part of the mainset not the 16. This will reduce the session by 800m.

What size pool? The session should work well in either a 25m or 50m pool. Swimming in a 33m pool? Instead of 50m swims I would swim 66m swims and start at 12. Overall volumes would be similar for 12/9/6/3 swims. Swim the warm up as 66FC into 33m drill/ fast/kick etc. In a 50m pool? Think of the warm up as distance in metres not lengths so you still punctuate the FC with a non FC activity at regular intervals.

What drills? Choice drills being demonstrated can be found at sessioninabottle.com/swim-videos

The difference between fast and steady? Fast should not be such an effort that technique disintegrates. Steady is just that, steady. You can talk between swims and do more if needed. There is nearly 4km on offer here and that should be enough to challenge most!

No swim toys? Try ‘fast drills’ like fists clenched, extension switch which rely less on fins. Or perform 10m of drill and have it flow in and out of full stroke.


Never be without a training session with a Session in a Bottle. Four distance options available. sessioninabottle.com

01 Cover October

Issue 54 October 2021

  • We Swim Proud: The LGBTQ+ experience of swimming outdoors
  • Autumn Adventures: The best places to wild swim this autumn
  • Crowning Glory: Courtney Paulk’s historic Double Triple Crown
  • Cassie Patten: What is the best style front crawl stroke for the open water?
  • Access All Areas: The problem of making lidos more accessible to disabled swimmers

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