Tuesday, May 22, 2007

Southern Vets League Basingstoke: 3000m

My first track race of the season was last night, running for Havant AC.

It had rained all day, was raining when we arrived, but the rain held off for the event. It was rather cool and the track was covered in puddles, but the conditions were OK for me.

The cool conditions may have been a factor in several muscle strains and tears though. Poor Rob pulled up in the 200m with a torn hamstring and Tom Buckner pulled a calf muscle in the steeplechase. I felt sorry for Tom as the announcer declared "And here we see ex-international steeplechaser Tom Buckner still showing good technique, despite his lack of pace". Cheek! Tom scored some good points though, but I think team captain Pete was a bit disappointed by the several DNFs dragging the men's score down.

Meanwhile, the women were doing somewhat better.

I watched Vicki and Amanda show everyone how it was done in the 800m and then it was my turn in the 3000m.

I had a good race, winning the B race, pacing well and knocking 14s off my PB. Teammate Bev took a half lap lead over me early on, but from there I seemed to keep pace with her. I tracked Winchester woman Jan for much of the race, but she pulled away on the last half lap. At least I didn't get lapped by (Winchester's) Karen Hazlitt this time, but she had done the Great Manchester run the previous day (in under 35 mins). You may ask how I finished behind 2 Winchester women and still won the B race - I don't know - I assume one of them was guesting. I did however lap another Winchester woman and lapped my W50 team mate Marilyn, who provided a good target in the finish straight. I just had to lap you Marilyn - sorry!

I finished in 11:42.4.
The age graded result was 78.7% (the older you get, the more you rely on age grading to tell you how you've done!)

Here are the splits:
92s 124bpm
94s 151bpm
94s 153bpm
93s 155bpm
93s 157bpm
94s 158bpm
94s 158bpm
46s 157bpm

You will notice that the last 200m is a slightly lower ave HR even though it was as fast a pace as the opening lap and faster than the penultimate lap. My HR dropped by 2 or 3 beats in the finish straight despite me pushing hard for the line, and presumably picking up speed (chasing Marilyn!). I can only assume this was some weird effect of going totally anaerobic and dropping the need for oxygen? I'm not sure, but it might be something to research.

It was a fraction slower than I'd hoped, but I had a fairly full week/weekend and didn't taper for the race. I'm pretty pleased with the result.

In the women's match we were winning by the time of the final event, the discus, which was still going on when we left. Well done team!

Sunday, May 20, 2007

Emsworth to Basingstoke Charity Relay 2007

Last Saturday 12th May the club ran the Emsworth Basingstoke Charity Relay in aid of Motor Neurone Disease. I've just got Jan's photos. Here they are:
The girls team:
The girls
The boys A team:
The boys A team
Dave leads off the boys A team:
Dave leads off
followed by Toby for the B team:
Toby follows for the B team
and Vicky for the girls
Vicky leads out the girls
Amanda takes over from Belinda at Chalton:
Amanda takes over from Belinda
Amanda then hands on to Susie. This is serious relay changeover stuff!:
Amanda then hands on to Susie
Belinda to Marilyn at West Worldham:
Belinda to Marilyn at West Worldham
Marilyn then hands to Shelly south of Alton:
Marilyn then hands to Shelly
It can be exciting stuff, but sometimes you're on your own:
Marilyn solo

The girls won their race against the other 3 (or 2?) girls teams. The boys A didn't manage to repeat their previous win, finishing 6th after some unfortunate navigation errors. The B team finished just behind us girls - sorry boys! (and girl).

We were so lucky with the weather - sun and no sign of rain, despite the soaking Basingstoke got earlier in the day. Great fun!

For a full description of the race, see the report from 2 years ago.

Thursday, May 10, 2007

Portsmouth Promenade 5k

Again I raced with a target in mind, and again I missed my target. This time though I was not disappointed as I had a great race.

The target was 20:00, one of my aims for 2007, which I'm sure I'll get as soon as I get the marathon out of my legs. I finished in 21:04 which I'm reasonably happy with given the conditions.

It was very windy! It was blowing a force 7, by my reckoning - not quite a gale but pretty hard to run into. We had much of the last 3km into the wind and it cost a lot of time.

My enjoyment of the race was saved though by my battle with Tina. I overtook Tina at the start, then she overtook me at 1km and I took her back shortly afterwards as we ran shoulder to shoulder round the Lido. She then took me at 3km as we struggled with the wind and she held the lead until the final run in. Helped by a couple of faster guys providing pacing targets I managed to get back to about 10m behind her as we weaved around the paths in the park. As we entered the final straight I still didn't think I was going to be able to catch her, but somehow I found an extra gear and pulled back 10m in a sprint for the line. I finished just ahead of Tina and turned what could have been another moan about weather conditions robbing me of a time, into a rewarding true run race.

Thank you Tina! I love this sort of racing and don't get too many chances to have such a close battle. I finished 2nd W45 which is far more important than the time as this is a 3-race series. I hope the rest of the series is as good as this one!


The splits:
3:54 147bpm wind behind
4:06 156bpm mostly behind, some buffeting
4:20 159bpm mostly in front
4:28 159bpm headwind all the way
4:11 158bpm some headwind

I think I paced reasonably well, but maybe I did fade a little in the last km as my HR dropped slightly.

I look forward to the next round in July where I will hopefully have a fresh, marathon-recovered, pair of legs and a proper crack at that 20-minute barrier (in windless conditions?)


We may have had a good team score as Gina finished ahead of me in 20:24ish (I think) and Sacha coming in behind me. We had at least 4 men running: Neil, Graham, Toby and Bob. Sorry if I didn't spot anyone else. Thanks to Marilyn and Kevin for their support.

The men's race was won by James Baker, with Sophie Morris of Windsor Slough and Eton winning the women's race with a time quite close to Lucy Elliott's course record - pretty good in such windy conditions.

Monday, May 07, 2007

Heart Rate Kinetics

I had an epiphany recently. It wasn't exactly a road to Damascus moment, but for someone obsessed with all things heart rate, it was another step towards my cardiac enlightenment.

For years I've recorded heart rates of each run, and plotted curves looking for trends and signs of improving performance. I'd always tended to ignore the first mile though, as it takes time for the heart rate to stabilise and provide any data that could be interpreted meaningfully.

Then the other day I read an article on VO2 kinetics, which indicated that maybe that first mile's data may not be so meaningless after all.

I've always understood heart rate to be a good indication of oxygen demand and lactate levels. While heart rate monitors are good for this in aerobic exercise, eg marathon pacing, there are times when they are not so useful, namely high level exercise and short duration events (intervals) where the HR hasn't stabilised.

To see how the HR ramps up at the start of the effort, here's my heart rate plot of the first kilometre of the Eastleigh 10k:
HR plot of Eastleigh 10k 1st kilometre

In this plot you can see the HR curve increasing exponentially up to a value of 146bpm by the end of the first km. As there isn't a stable HR level to pace off, I'd always assumed the initial data was best ignored.

However, a Peak Performance article reveals that this data may be useful after all.

The thing I'd never quite understood is that if HR indicates oxygen demand, then why is the oxygen demand apparently less during the opening minutes? Surely if you are running aerobically at an even effort then oxygen demand should be constant? I'd assumed that HR wasn't a reliable indicator of oxygen demand until after a few minutes when you'd warmed up.

The revelation came seeing a VO2 plot in the pages of Peak Performance of the initial minutes of high intensity exercise. This was a plot of the actual oxygen consumption, measured using a face mask and oxygen analyser, rather than a heart rate plot. The thing was though that it looked the same as the above. Oxygen demand increased exponentially just as HR did. Heart rate wasn't such a bad indicator of oxygen demand after all.

So if the effort is constant, but oxygen demand isn't, what's going on?

It takes a while for the muscles to 'warm up' and for the mitochondria to all come on line and process the much needed oxygen. This means that for the first few minutes of exercise there is an oxygen debt. In the absence of an adequate oxygen supply the muscles are forced to produce energy anaerobically, and this means:

Lactate!

Ah, music to my ears!

Clearly then, the faster the muscles get up to their maximum oxygen uptake the better, as there will be a smaller oxygen debt and less lactate build up. Any build up of lactate early on will have a major impact on subsequent performance as the muscle's efficiency is reduced. The smaller the oxygen debt the better.

This whole process of oxygen uptake is known as 'VO2 kinetics'.

So how do we maximise our VO2 kinetics? The most effective way is a good warmup. Allow me to demonstrate.

Here is a HR plot of a treadmill session I did on Saturday. The blue line shows 4 minutes of effort at 14.5kph. It was a little dodgy going straight to 10k pace without a warmup so I did at least do some mobility exercises. I was careful to keep my HR down though so that I was performing from cold. After the first effort I had 5 minutes of standing recovery to get my HR down quickly. The green plot shows a second 14.5kph effort of 4 minutes following the 5 minute recovery. The first effort had thus acted as a warmup. The red dotted curve I'll explain later.

Heart rate curve of 2 efforts of 4mins of 14.5kph treadmill running, 5min recovery between

A word of caution: these are HR plots not VO2 plots. HR will give a fair indication of oxygen uptake as the greater the demand for oxygen the faster the heart has to beat, but HR and VO2 are not the same - heat can affect HR as blood is pumped to the skin for cooling and causing a restricted oxygen supply to the muscles. Here though, with short efforts and a full recovery, it is likely that both efforts are being done in similar conditions with similar oxygen transport.

Having said that, clearly the green plot shows a faster increase in HR. The slope of the 2 curves is initially similar, with a small lag on the blue curve, but then there is something of a blip on the blue curve and the gap between the 2 increases somewhat. It is a fair bet that the oxygen debt for the second curve is less than the first. Personally, the second effort felt a lot more comfortable. I've noticed this effect too when running fast intervals - it takes 2 or 3 efforts before my legs feel comfortable, despite them all being the same pace.

The dotted red line in the above plot is a mathematical plot - an exponential curve with a time constant of 25s. What this means is that every 25s the gap between the current HR value and the value it is tending towards, 147bpm in this case, is halved. My time constant is thus about 25s.

Clearly the smaller one's time constant the better. The PP article made it clear that a good warmup will influence this, but also that endurance training can improve the time constant. Current research does not show what sort of training might have the best influence though.

I was intrigued to learn that the person with the fastest measured VO2 kinetics is Paula Radcliffe with a time constant of 8-9s. Whether this is down to training or genetics is unknown. Maybe I should try 140-mile weeks and test again.

Of course my time constant is measuring HR kinetics and not necessarily VO2 kinetics - they may not be the same, though I can assure you I don't have a VO2 time constant of 9s!


So what more can I learn from this data? It appears that we have a way of quantifying the effects of a warmup. I wouldn't call 4mins of 10k pace followed by 5mins standing, the best warmup. What I want to do is repeat this test with my usual warmup of 10mins jogging followed by some 30s sprints picking up the pace. In order to influence the oxygen uptake one has to warmup around threshold pace or faster in order to generate a bit of lactate. It's important to have a bit of recovery before the race (or test) though, as otherwise the warmup might impact the performance. I think my standard warmup fits the bill, so it will be interesting to see how it affects the test.

Can I improve the effectiveness of my warmup? With the track season coming up, I hope I can. Watch this space for details.

Reference: Peak Performance Number 245: Oxygen kinetics - start smart for a mean finish!