Swim Sessions: Threshold 25s + 100s
I love a threshold swim session. A session where you raise your heart rate – and then keep it there for a good length of time!
A mental and physical challenge, which is hugely satisfying when it is all over!
We did a different type of threshold session recently. Instead of a 20 x 100m set (or a variation of this), we did some 25s and 100s. This set was 2,000m of pretty hard work.
During the set we were aiming for:
- Strong Pace
- Sustainable Effort
- Sound Technique
- Strong Mental Focus
I think we ticked all of those boxes!
“That was my type of session!”
“Really enjoyed this session including the short intervals on the 25s. Felt good throughout and did a quicker average than I was expecting. Probably the most consistent and smoothest session I can remember.”
“Might have been a 100m PB – 1.30”
The Session
Warm Up (200m)
2 x 100m smooth and relaxed (20s)
Main Set (2200m)
Two sets of …
20 x 25m – a strong pace that is just about sustainable for all 20 x 25m (15s)
5 x 100m – a strong pace that is just about sustainable for all 5 x 100m (30s)
4 x 25m – easy (15s)
Cool Down
Easy swimming to finish
Scaling
We reduced the session slightly for some of our lanes. It was 16 x 25m and 4 x 100m instead.

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Swim Sessions: Threshold 25s + 100s
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