Wednesday, 6 May 2009

Treadmill torture at the Human Performance Centre

Yesterday I went to the Human Performance Centre at Lincoln University for my third treadmill session. My first and second tests were in May and December last year. I am one of several ultra runners in the UK who volunteered as Paul Murgatroyd's research subjects.

Paul, from the Department of Sport, Coaching and Exercise Science, is analysing ultra runners and the intensity relative to our natural ability at which we run our ultras. So far he has carried out two analyses in the field, where we are monitored during the course of an ultra. The first one was the 50-mile Rowbotham's Round Rotherham last December and the second was the 36-mile Calderdale Hike a few weeks ago. In order to find our natural ability we must be put through our paces on the treadmill. In order to get an accurate measure relative to the field study results, we must be analysed close to those events. Only then can accurate comparisons be made, hence the need for three treadmill sessions so far. I can tell you it is not a comfortable experience. For a start, the intensity means that you are well advised to fast beforehand so that you do it on an empty stomach, otherwise effort-induced nausea will surely result in you giving less than your best.

The laboratory is modern and impressively equipped. The treadmill is extremely spacious, since it is designed to accommodate bicycles and wheelchairs. I seem to recall that it can go up to 40mph. It's a serious piece of kit. A runner feels rather lonely and exposed on such a wide expanse of belt. “Do I run on the left, right or down the middle? I think I'll position myself close to the emergency stop button, wherever that is.”

First, a finger prick draws a spot of blood to measure resting blood lactate level. A chest strap detects heart rate and transmits it to the monitoring equipment. A quite lengthy warm-up run gives Paul an idea of heart rate versus speed so he has an idea of what speed to start the calibration test.

A face mask is fitted, which monitors flow rate of inhaled / exhaled air and samples the exhaled air for carbon dioxide content, then the calibration test can begin. The calibration test involves three-minute intervals at zero incline and speeds that increase by 1km/h each time. A blood sample is taken close to the end of each interval to monitor blood lactate. The test continues until two turn points in blood lactate (Lactate Threshold and Lactate Turn Point) have revealed themselves. Holding the left hand still every three minutes for the stab-and-sample can be fun as the belt forces you to run ever faster. It's tough, but not as tough as the final test, the run-to-the-point-of-collapse test.

After a cross-legged recovery sit-down on the treadmill I'm up again, face mask re-fitted and I'm ready to roll. The speed is fixed at 2km/h slower than the maximum speed in the calibration test but the incline increases by 1% every minute. The idea is to keep going until you can't do it any more.

It seems quite comfortable at first, almost sedate. I concentrate on my stride, lengthening it, which slows it down. It seems to make it easier and more bearable. I need to keep doing that for as long as possible. The gradient is increasing. It still feels comfortable. Thoughts are flitting through my mind. Some thoughts are calming but most are not. “Think calming thoughts. Hold it together.” The gradient increases further. I need something to take my mind off the creeping discomfort. I stare at the picture on the wall in front of me with the cyclist on the very treadmill I'm running on. The researchers are monitoring the cyclist intently. I suppose Paul must be doing a similar thing with me but he is out of my vision. I can't look sideways. I hear his voice giving encouragement but it never seems enough. There are too many pauses. I need a running commentary, a bigger distraction, something more intense. Perhaps a sergeant major bellowing his orders every few seconds. My gaze fixes on the big chromium electric fan on the table in front of me blowing its cooling air onto my shirtless body. The temperature is only 18°C but I'd be burning up without the fan.

The gradient continues to increase. I can really feel myself running uphill now. I'm breathing very heavily. I can't keep this up much longer. The long, controlled strides are falling apart. It has become an uphill struggle. I notice the intense nausea is not enveloping me like it did last time. The fasting must have worked well. Thirty seconds seem like a lifetime; it takes forever for Paul to say, “Half way through”. I want to stop but I must keep going at least to the end of this stage. I'm dragging my feet upwards for the next enforced stride that must occur at the allotted time, followed by the next, and the next..... I'm on the brink. I hear “Just ten more seconds to the end of this stage. See how far you can go in the next stage”, plus various other encouraging words. Ten seconds are a lifetime now. I just about make it to the end of the stage and indicate a halt to Paul. I could not have reached out to my right to hit the emergency stop button. The belt quickly ramps down to a stop and I remain standing for just long enough for Paul to remove the mask before I descend rapidly to the cross-legged recovery position. My panting slows rapidly and within thirty seconds I'm up to take a few swigs from my water bottle. I managed to take it further than ever before.

The results came through today. I'm not getting any faster but the lactate turn points are increasing and my heart rate is reducing markedly – all good news and confirmation of what I have observed on the events. I can sustain a respectable pace for longer, with the correct fuelling.

'Running economy' (amount of oxygen used compared with body mass compared with running speed) is another matter. It was unbelievably bad before and has just got worse, leaving me not far off the bottom of the scale and well down in the bottom of six categories, described as “Poor”. It can't get much worse.
I went further in the test this time so I processed more oxygen, I'm a lightweight and I can't run particularly fast, so my 'running economy' result is diabolical. It's a marvel I can run at all, let alone run ultras. Perhaps I should put some weight on to bring my 'running economy' figure down. More pizza washed down with lashings of beer, perhaps? As if I don't do that already – just replace lashings of beer with lashings of wine and live it up a little. I'll 'ave the lot and I shan't be as sick as a dog in the morning.


  1. Nick - I picked up your comment on my blog after I posted the RR50 HR Printout on there. Your descriptions of the sessions is spot on!

    I was still under the influence of RR50 and The Beacon Ultra from the days previous at my last session in Lincoln and not a lot had changed (I think my lactate threshold had dropped a fraction) but my running economy shot right up from "if it's that bad how do I get away with this" to "why aren't you much much faster!?!".

    Amazing how we are all different!

  2. Blimey the tread mill sounds worse than the racing pain! How long is the test - do you want to talk about it on Runfurther? Be a good article to get you all putting something in about your experiences/improvements?

  3. Oops forgot to say well done at the weekend and good to see how well you are running and just how much of a mad person you are - takes one to know one eh!!!

  4. Mike, all of my running economy results have been the "how do I get away with this" type. Paul gave me to understand that they can be all over the place irrespective of whether you're elite or a plodder like I am.

  5. Karen, of course the sessions are more painful. I never push myself that hard in races. I am a plodder after all. The sessions for me last 1.5 hours typically.
    It was good to see you at the Fellsman. I look forward to seeing the pictures. Good leg massage too.