Muscular Pain and Muscle Growth

Muscular pain, what is it exactly? Where does it come from? How long does it last? Can I train my horse when he is suffering with muscular pain? Do the muscles of my horse grow when he has muscular pain? How fast will strength of the muscles reduce if I stop training? Many equestrians ask these questions. You can find the answers in this blog.

A small test

We were very curious as to if we could to capture muscular pain in photo form, so we carried out a small test. We followed a mare for three days, and filmed her trotting in a straight line on the road. On Day 1, she had a jumping lesson, Days 2 and 3, she was in her field throughout the day (08:00 to 19:30) and had a recovery training on Day 2. In trot, we saw the biggest differences in movement. Below is an image with an overview of the three days. You can see the biggest difference in the angle of the front knee (carpus) - The larger the number of the angle, the less the front knee is bent. In the picture, it is visible that the mare's front knee on Day 2 is bent the least, so the angle is the largest. The cause of this could have been muscular pain.

We also observed a difference in the bending of the joints in the lower leg:

Again, the hip and knee were the least bent. While the hock was used with the same angulation on all three days.

So, the horse in the pictures, probably experienced muscular pain on Day 2. As the joints are least bent on this day.

This has, of course, been a small test for us, but to draw a real conclusion from these findings, more research is required. In addition, there are other symptoms of muscular pain, which did not investigate.

Varying types of pain during and after training.

During and after a training, horses can experience three different types of pain:

1. Acidification: This is when lactate is not able to neutralize the acid that is released during a training.

2. Muscle pain: swelling and inflammation that eventually leads to desired muscle growth, is visible one to two days after training.

3. Tendon and joint pain: The horse can experience this pain during and after training, when warming-up is inadequate.

Muscular pain can lead to muscle restoration.

In the build-up phase of training, in which you want to grow your horse's muscles, you train above the fitness level. This causes cracks in the muscles, which is referred to as ‘micro-damage’. The next step is that inflammation occurs due to this, which can leads eventually to muscle growth. In addition, muscle proteins are also produced, these provide recovery and growth.

A horse with muscular pain will sometimes appear somewhat stiff at the beginning of the training. It will be less supple, and has more difficulty in flexing and bending. The horse will also be slightly reluctant to go forward.

After muscular pain comes muscle growth.

As you train longer at the same intensity, the muscular pain decreases and muscle growth (called hypertrophy) increases.

Presumably a muscle grows as follows:

In the first week of starting with a more intensive training schedule, your horse will incur a relatively large amount of micro-damage and a little muscle growth. The muscle will create more recovery proteins, and less growth proteins.

If you have trained at the same intensity for three weeks, you’ll see more muscle growth and less micro-damage.

After ten weeks of training at the same intensity, the speed of muscle growth increases and the muscular pain diminishes. The proteins that the muscle produces will now be more focused on muscle growth.

This theory is derived from a humane research.

A certain degree of muscular pain is, therefore, needed indirectly for muscle growth. However, muscular pain only will not cause muscle growth. It is the chain reaction that ensures muscle growth when you train at the same level for two to three weeks.

How long does muscular pain actually last?

In the case of micro-damage, your horse can experience the largest amount of muscular pain, 24 to 48 hours after the training. During this period, the process to restore the muscles is at its peak. During this process, inflammatory cells are needed to repair the muscle. This can sometimes be visible in hot and swollen muscles.

Example 1 Building up training:

On Monday, you attended a dressage lesson with an intensity of 80, while your horse’s fitness level is 40. You chose this, because you want your horse to achieve a higher level of fitness. The best time to train again is then on Wednesday. This is because the time when muscle pain is at its peak (24 hours) elapsed. In the intervening day, you can ask your horse to do light gymnastic exercises, this is called recovery training. These trainings are under your horse’s fitness level. The screenshot alongside shows how the training and fitness level appear in Ipos Technology’s Training App. The line represents the fitness level, and the bars are the trainings.

Example 2 Competition:

It's Friday. On Sunday, you have a dressage competition. You still also have a dressage lesson planned before this, but you know that these trainings are always very intensive for your horse. If you go ahead with the high intensity dressage lesson, it could be that your horse will have muscular pain at the time of the competition, and is likely to not be able to complete the dressage test to the best of its abilities, because of it. In this scenario, it is better to keep the intensity level of your dressage training low, and ensure you don’t rise above your horse’s fitness level. In this way, you avoid the scenario in which your horse might have muscular pain on Sunday for the competition. The competition itself should not be above your fitness level.

What happens if you train again too quickly?

The chances of (minor) injuries will increase if you train your horse too early and too intensely. If you train while your horse still has muscular pain, the micro-damage in the muscles can accumulate. In this scenario, the horse’s body has not yet had time enough to repair the damage.

If the training is too heavy (for example , it has a training load of 80, while your horse’s fitness level is 40), while your horse has not recovered yet from a previous training, your horse may show signs of disobedience, and may not be willing to go forward or bend as usual. Ipos Technology’s Training App can help you to load your horse the right amount on the right day. The App calculates your horse’s fitness level. In between discipline-specific training, you add a light, recovery training. These training are typically at, or below your horse’s fitness level.

What happens if you train too late?

It's never bad to plan an extra day of rest. The muscle mass only decreases after two weeks of rest. The longer you wait with exercising, the faster muscle mass decreases. So, it takes quite a long time for muscle mass or muscular strength to diminish. With a good training schedule, you will find out that in the end you may not have to train as much, or as heavily as you are used to, and yet you can still obtain a higher level of fitness of the horse.


· Muscular pain is most often the recovery process of muscle damage from training.

· The increase in muscle occurs fastest after ten or more weeks of training.

· There are several types of pain during and/or after a training.

· Muscle pain is worse between 24 and 48 hours after the training.

· When you train too early after an intense training, the muscle damage

accumulates, and the risk of injuries increases.

· Muscle mass diminishes only after two weeks of no training.

· Muscle strength decreases after three to four weeks of no training.


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