[I’ve gone and done it again. I wrote 90% of this post then never got around to finishing and posting it, so it’s a little out of date but still relevant. So here it is…]
So, I’ve almost managed 2 months of running
slowly aerobically. I’ve done a race. And I’ve got some good stats to show whether it’s all working or not so far for me.
Review of the Runs
This post covers the time from mid November when I started through to 6th January, over which time I ran 310 miles. I’ve downloaded some data, doodled some graphs and even made up a new metric which I think may go some way towards quantifying aerobic fitness.
First, here’s the average heart rate chart for my runs:
Apart from a couple of blips, most runs are pretty close to 140bpm on average. The two blips were deliberately faster – the first was a run with a target pace of 160bpm, and the second was the Broadstone Quarter Marathon. On the whole, I’ve been quite well behaved considering that’s over 300 miles of running!
Getting a bit more interesting is the average pace:
I’ve taken out the two faster runs so we’re just looking at the approx 140bpm average runs. The blue trend line shows that there’s a definite improvement in pace over the time period – from about 10:23 pace to around 9:34 pace. So this is an improvement of around 50 second per mile at the same heart rate over 310 miles of slow running. If I can keep the mileage up, I’d like to think I could get the (average) pace under 9 minutes per mile before the end of February. If the trend continues, I might be looking at a pace of around 8 minutes per mile at 140bpm by April/May time, although my gut feeling is that the improvement will diminish as my aerobic system becomes more efficient so there are less gains to be made.
Beats per Mile
I’ve also plotted the number of beats over a mile. It’s calculated by multiplying the average heart rate by the average run pace. So if you have an average heart rate of 140bpm and run a 10 minute mile, then the beats per mile is 140*10 so 1400 beats.
I’d love to be able to run at 7 minute miles with a heart rate of 140bpm, which would equate to 980 beats per mile. Looking at the chart above, back in November I was running at a bit over 1400 beats per mile, and now in January I’m running at a little uner 1350 beats per mile.
If I’m a bit more realistic about my target and hope for 8 minute miling at 140bpm, then I’m needing to drop to 1120 beats/mile. At the current trend rate, I might hope to get there in about 18 weeks which is quite exciting!
Weight Loss over the measured period
It’s worth noting that I’ve lost about 8lb over the period of the results above, which is going to have an impact on my running performance, so the estimated rate of improvement is likely to drop. Having said that, I’m planning on losing about the same weight over the next 7 weeks, so when I give an update the in about that time the conditions should be fairly similar.
How have I been running?
Well, it’s been interesting. Initially quite frustrating with lots of slow, slow running – which was fine – but as I got towards the end of runs I was finding my heart rate climbing (I live at the top of a hill so every run ends with climbs) and the frustration this caused meant my heart rate was going up even more.
However, as the charts show above, things are improving and the improvement seems to be gaining rapidity. I did make a conscious decision in late December to run about 10-20% of my weekly mileage at a higher pace – my chosen target was 160bpm. In the data above I only did this once and that was a bit interrupted so not a clean run, but the intention is to carry this through as it seems that after a faster burst there seems to be an improvement in pace running at lower heart race for the next 1 or 2 runs.
I mentioned above about getting a bit stressed towards the end of runs when the watch keeps beeping, and I’m sure this pushes the heart rate up a few beats more, making the watch beep even more! To counter than I’ve started trying to do a sort of meditation on the run – slower breathing, relaxing shoulders and arms and just chilling out a bit and it does seem to work.
For the first month I slowed a lot for most hills, but in the last week or so I’ve begun to just run slower up hills that aren’t too long and if I go over my target max HR for a minute or so I don’t mind – it all comes down again quickly, and makes for a less stressful run.
One other thing I’ve noticed is that my cadence has increased. I always tried to run at an average of 180 steps per minute, but usually ended up between 170-175. Over the past weeks, my cadence has naturally climbed and is now typically 180-182 steps per minute for most runs and I expect it to keep climbing. I think my form has changed a little to deal with the slower running and stayed that was despite the improvements in pace.
Broadstone Quarter Marathon
The last thing to comment on is the Broadstone Quarter Marathon. This was a target race on 1st January to test the effect of 6-7 weeks of aerobic training, and I just intended to run hard and see what happened.
A PB is what happened. By around 3.5 minutes! (from around 49:30 to 46:04 – average of 7:05/mile for the race) I’m delighted with that as you can expect, and that was all based on almost no speedwork whatsoever. Here are my thoughts from the race:
- The aerobic training seems to have made me be able to keep going for longer. There was no real fade, and I could still push hard at the end from a fitness point of view.
- My legs ached towards the end, so I think although there are significant fitness gains from aerobic training, the muscles aren’t used to running hard and fast and were objecting.
- Running at 6:30 pace didn’t actually feel all that hard. In the past, I certainly knew I was running at that pace. On this race, I felt fast but seemed to be using less effort.
So, all in all, it’s a great result at this point in training.
I’m going to keep running like this, but add in the 10-20% faster (160bpm) running once a week through to March when I have my first ultra of the year. I’ll up the distance in training and get a few 20-30 mile runs in between now and then, but keep the focus on slow, enjoyable aerobic training and hopefully continue to see improvements in pace at a specific heart rate.
I’ll let you know how I get on in a few weeks…