Cardiac drift test

I talked about a cardiac drift test in my Cardiac Drift posting. Last night I redid the test, still at around 80%maxHR - 140bpm, but at the much faster pace I am now running at.

The plan was to warm up for about a mile, then run continuous laps of a neighbourhood circuit of 1.5miles, taking split times and average HR for each lap. It was very cold last night and it took me a couple of miles to feel settled, so my pace was a little off for the first lap. I soon settled at around 8:25/mile and 140bpm. There was a noticeable headwind for a third of the lap: I don't think this had too much of an effect, but may have slowed me from the 8:20/mile I had tried to run at.

As ever the HR plots are pretty but not as meaningful as the lap data. Here's the plot:

And here are the lap details:

1.5-mile continuous laps. 1 mile warm up/cool down not included

Lap	Lap time	Mins/mile	bpm
1	12:56	8:37	135
2	12:34	8:22	140
3	12:42	8:27	141
4	12:40	8:26	140
5	12:35	8:23	141

So I can sustain 140bpm for well over an hour with no sign of cardiac drift! This means that my Maximum Steady State, or marathon pace, is at least 140bpm and may be higher.

The great thing for me is the pace I maintained. 8:25/mile feels really quick, but I can keep it going for a long time. This is much quicker than last time I tried this test, although I suspected then that I wasn't fully recovered from illness.

I shall now try training at a slightly higher heart rate and redo the test in a few weeks at a faster pace.


This was really good news last night, but it's tempered with the bad news that I've injured my left soleus muscle. It has been very cold the last few days and this may have contributed. I'm getting it checked tomorrow, so will try to reserve judgement till then.