Interval Training for Horses

I just joined Orange Theory fitness with is interval training for couch potatoes with heart rate monitors so you can get into the "orange zone" to increase your aerobic fitness and burn more fat. As I was on the tread mill, listening to the trainer say "keep going, this should feel uncomfortable", I thought about our horses and how important it is, even more so than for humans, to be properly conditioned so they can not only perform safely at their best but be able to perform at a higher level than we compete so they don't feel uncomfortable ! We can't inspire them to push on with motivational quotes, dance music and the hopes of 6 pack abs. 

Interval training is a workout composed of short burst of intense work followed by partial recovery periods with the goal of increasing cardiovascular fitness, strength and speed. Interval training increases aerobic fitness faster so the horse can exercise for longer periods of time before lactic acid and fatigue set in (pre-tying up). 

To understand the benefits of interval training we need to know about slow and fast twitch muscle fibers. 

Slow twitch fibers (type 1) are for long, slow work. They use oxygen to produce lots of energy for long periods of time, aerobic metabolism. The muscles you use for standing, or sitting up are mostly slow twitch fibers. For example the intrinsic muscles of your spine. They are happy to stay engaged at low level for the day. 

Fast twitch fibers (type 2b) are for high speed, strong contractions, like sprinting or hill climbing. They generate energy without oxygen, anaerobic metabolism. They use the glycogen stored in the muscles for energy and produce lactic acid as a by product and can lead to pain and cramping (tying up). Your gluteals and thighs have lots of fast twitch fibers. Do a few squats or run some stairs and the burning you feel is your fast twitch muscles fatiguing. 

Then of course, there are some muscle fibers that have both characteristics (type 2a). These are use both aerobic and anaerobic metabolism. Your gluteals and thighs also have lots of intermediate fibers to so you can run or ride for long periods of time. 

Different breeds have have different ratios of slow and fast twitch muscles. Most TBs and Qh have around 90% fast twitch fibers to 10 %. They are bred for sprinting. While most draft breeds are more like 60%:40% fast to slow so they can walk all day. Arabians are somewhere in between, 75%:25% fast to slow which is why they excell at endurance racing.  

Exercise can't change the amount of fast twitch to slow twitch fibers but it can increase the size and working capacity of the types of fibers we want to train for. Say we want to get ready for our first CDE, interval training can help us build our slow twitch for endurance and our fast twitch for speed and strength in the hazards. Just road work at a 14 kph trot will improve endurance but not improve your times because it targets your slow twitch muscle. A workout that includes a 15 min walk/trot warm up with some 3-5 min trot and canter sets at varying speeds with 1 min walk breaks can rapidly increase fitness by building up those fast twitch fibers too. 

Now we have some questions we need to answer before we design our workout plan.
1. breed type
2. discipline
3. time line
4. Attitude

In part 2, we will walk you through an exercise plan.