More Warming Up Specifics

Moving right along, our mythical chestnut has done an above average American track warm up and we're considering whether the warm up was sufficient for max performance and injury prevention:

3. Engagement of energy pathways--ATP, glycogen, O2 uptake by cell mitochondria, increasing rate of metabolism and efficiency. I'd have to take out my physiology book to recall the exact biology in these processes. Just a brief synopsis from memory: motion is produced by muscle contraction. Muscle contraction happens when individual muscle cells shorten the overall muscle tissue by moving against each other. The muscle cells have little "prongs" which rub against each other and catch with the neighboring cell. When the individual cells contract the prongs catch with the prongs off another cell and so on, cell on cell, shortening the entire muscle.

The above process takes energy: the conversion of fuel to heat.

The initial fuel used by muscle cells for about 15 seconds is called ATP which is produced within the nucleus of the cell by various nutritional elements involving conversion of choline, carnetine and a few other catalysts. After the ATP stores run out the muscle cell commences to fuel itself by anaerobic (non-O2) processes involving glycolosis--the burning of sugar that 1. has been stored in the cell, or 2. is extracted from the blood stream. There is enough glycogen available to allow anaerobic metabolism to last 1-1.5 minutes depending on the state of conditioning.

As available glycogen is quickly depleted each cell attempts to convert to aerobic metabolism which is the utilization or burning of O2. Aerobic metabolism tends to kick in 1-1.5 minutes after the start of activity.

Of course any activity from rest begins to engage the metabolic processes. The more intense the activity the greater the speed at which the mitochondria in the cells respond.

For purposes of warm up--and here I start to get into speculation from memory--and we're talking about the sort of slow easy warm up being experienced by our chestnut--this sort of activity probably leaves cell ATP in place and can be largely supported merely by the burning off cell glycogen.

Without a doubt our chestnut's warm up is sufficient to alert the anaerobic mechanisms and get them started. And to a degree I'd suppose O2 metabolism is also placed on alert.

My guess, however, is that "cantering" or "trotting" is woefully inefficient to have the energy processes fully ready for the charge out of the gate. As you may imagine "metabolism" through it's various channels is other than instantaneous. It takes at least seconds for any of these processes to kick in. Most races due to distance and time spent in running are 75-100% anaerobic with O2 mechanisms starting to kick in probably at 45 seconds into the race.

All the energy systems have been somewhat alerted by the chestnut's warm up. That these mechanisms are at peak efficiency and ready to fully work from the gate would require a far more event specific warm up than our chestnut will get. My guess is that cell metabolism begins to reach peak efficiency--given this sort of warm up--about 45 seconds to 1 minute into the race. Essentially, with the North American warm up the horse leaves the gate running on adrenalin with its metabolic processes only fully engaged fairly far into the race.

How many horses hit the wall of fuel insufficiency because their metabolism engages late or has yet to engage at all (O2) due to insufficient warm up. Another principle of physiology is that the better trained the horse the less of the various fuels are absolutely necessary. The better trained horses will last longer with this warm up, but every horse will perform less efficiently for most of the race simply due to insufficiency in the warm up process. It is when I consider this stuff specifically that I really get p_ss_d off watching these idiots in pre-race warm ups. And, please trust me on this one, I'm just starting to get p_ss_d. You'll see far more significant reasons for extreme anger in the coming posts.

Training:
We've had a nice week training wise. Had to trot Sunday and Monday due to weather but have been galloping since. Farm breezes scheduled for tomorrow, Sunday. I'm encouraged by this and highly frustrated. This is what we should have been doing in February. Luckily none of my boys except the two year old have missed a day of training as it's been available, and so we have a high rate of "acquisition" from each training session and moving forward. Racing is linear--it never stops and continues right along. And, so will we, and see what develops down the road. Realistically we're about 30 days away from adequate racing performance for the oldsters.
Amart:
Wed. 6/13/07 4x3f slow gallop riderless. 7 min walk under tack.
Thurs. 6/14/07 5x3f slow gallop riderless, looking weak. tack day off.
Fri. 6/15/07 5x3f gallop, mostly snappy riderless. much stronger today, looking better. he sped things up on his own. 8 min. walk under tack