Sunday, 7 December 2014

Vo2 Testing

Vo2 testing is not something I have focussed on much as an athlete. The only time I have ever participated in the testings are for pre-altitude camps with British Athletics – although the information does fascinate me. My first ever test was in December 2012 followed up in March 2013 after spending a few weeks at altitude – the difference was quite substantial.

Naturally my body is very good with dealing with lactic and I hardly produce any - which co-insides with a marathon runners profile (supposedly!) - horrible to learn that the marathon is most suited to my physiology. Awful news to my ears.

For those who aren't familiar with what a sub maximal Vo2 test consists of – you are running on a treadmill over 6-8 different stages. I began at 7 minute miles which should be relatively easy for 3 minutes of running. This is then repeated at increasing speeds down to around 4.50 minute miles. A mask is covering your face to measure the volume of air expired along with the percentages of oxygen and carbon dioxide in the expired air. It's a little uncomfortable to run with but necessary for the testing. A heart rate monitor is also used to keep an eye on heart rate zones. After every 3minute run, the lactic in your blood is tested using a prick to your ear lobe.

The Vo2 Max test – takes the athlete to near their maximal limit. In the past, I have done it with increasing speed due to breaking my foot but this time around I did it on elevation – which I found much more difficult. The max tests continues you running on the treadmill at a quick enough speed but every minute the elevation increases by a percent.

My Vo2 capacity was pretty average for an athlete but my running economy was pretty good. (Find some explanations below!) The most unique quality is perhaps that I couldn't increase my lactic level to above 4 throughout the entire sub-max test until the final stage.

Perhaps the most interesting part and helpful piece of information for me are my heart rate zones. The tests give guidelines of what your heart rates should be on easy recovery runs, tempo runs and in sessions. I perhaps run my easy runs a little too slow – averaging 7 minutes or slower but my heart rate is quite low at 143 average – for the time being though – i'll stick to what i'm doing as I find the recovery keeps me fresh for sessions. I have been running my tempo's a little too slow so that is something I will definitely be aiming to improve on over the next few months.

This time around, I repeated the same test from 2012/13 to see what shape I was in coming into these winter months off such an awful summer season. I have been feeling much better since my break with no illnesses or viruses to report which is the first time i've been healthy in around 16 months! My tests came back better than ever – even though I haven't been exposed to altitude all year and have had to miss the first Kenyan Camp due to a heart complaint. So all is looking good for the upcoming indoor season – hopefully I can return to some sort of form and finally break some PB's!

For people wanting a little bit more in-depth stats. Here is the information we are given as athletes:

Lactate Threshold (LT): This is the first increase in blood [La] above baseline values. The speed at the LT is a strong predictor of the average speed that can be sustained in the marathon. The speed and heart rate at the LT are also useful in defining the transition between “easy” and “steady” running (see section 5 below).

Lactate Turnpoint (LTP): The LTP is the running speed at which there is a distinct “sudden and sustained” breakpoint in blood [La]. Typically, this occurs at 2.0-4.0 mM. The LTP tends to occur at ~ 1-2 km/h above the LT (the difference is smaller in longer distance specialists and larger in middle-distance runners). The LTP can also be used to define the transition between “steady” and “threshold” running (see section 5 below).

Running economy: This is the VO2 required to run at sub-maximal speeds. Running economy tends to be better in elite runners (i.e. their VO2 is lower at a given speed) and it is associated with improved performance. A common method for assessing an athlete’s running economy is to look at the VO2 in ml/kg/min at 16.0 km/h and 1 % grade (i.e. 6:00 min/mile pace). The average in well trained runners at this speed is 52 ml/kg/min. Running economy can also be expressed in units of mL O2/kg/km. Irrespective of running speed, the average economy is 200 mL O2/kg/km. 

On 3 dates. Oct'14,  Mar'13, Dec'12
VO2max: This remains an important measure of performance capability in middle and long distance running. While factors such as economy and LT/LTP can partially compensate for a relatively poor max in elite groups, entry to those elite groups is still limited by VO2max (i.e. the highest rate at which ATP can be resynthesised aerobically). It should be noted that VO2max tends to be highest in athletes who specialise in events that are run close to VO2max (that is, 3000 m and 5000 m). Other factors may be more important at shorter and longer distances.
The speed at VO2max (vVO2max): The vVO2max can be useful in predicting performance over 3000 m (and also 1500 and 5000 m). vVO2max is simply calculated by multiplying the VO2max (in mL/kg/min) by 60 and divided by the mean running economy determined during the first 4-5 stages of the treadmill test (in mL O2/kg/km).

Training zones: The speed and HR training zones given below are based around physiological landmarks (see explanation to the left) - the precise boundaries are defined according to the thresholds we’ve established today.
When @Sea level: Speed is the preferred option to monitor the correct intensity of your session. When @Altitude: It is important to realise that speed zones wont reflect the actual intensity zone so you will need to use the heart rate zones in this circumstance. Remember - it takes a good few minutes (3 to 5 min) for HR to come up to the level required. 

1 comment:

  1. WOW that's interesting... Now don't be scared of marathon's they are so much fun, and you don't need to run one for years. I wouldn't run one till I had run all the PB's I thought I could!

    No I'm excited to here about the upcoming races and to see those PB's!