My resting heart rate was nearly back to normal this morning after being raised by around 20% for the first half of the week. I'm assuming that the strain came from the sequence of Saturday run, Monday swim, Tuesday run and Wednesday run and circuits. At least a clear day made a major impact on reseting it.
After finishing a little early at work I went for a swim with the goal being to do sets of two lengths. That worked fairly well although I took longish rests between them. After 10 or so sets I put my mind to doing a set of 3 lengths and actually did a block of 5 or 6; it's not all that clear from my data. A key result though was managing the final 3 lengths in just under 3 minutes. My goal is to improve my technique and fitness to achieve 1km in a 30 minutes total so this is a step in the right direction.