Muscle soreness and stiffness in horses: how can you support recovery?

A horse cannot tell you that its muscles are sore after intensive training, competition or other physical activity. You might notice it when your horse feels stiff during the next training session or is less enthusiastic than usual when turned out into the pasture.

Some inflammation in the muscles is part of the adaptation to training. However, good training, enough recovery and a suitable, balanced ration are important to support your horse’s health, performance and recovery in both the short and long term.

How do muscles respond to exercise?

During exercise, small inflammations occur in the muscle tissue and stress hormones are released. Inflammation is the body’s protective response to disruptions in tissue homeostasis, the process by which the body maintains a stable condition within the tissue.

This inflammatory response is necessary for adaptations resulting from training, such as muscle growth.

Horses do not produce new muscle cells through training. Instead, the existing muscle cells develop and become stronger in response to the small inflammations caused by exercise. This process is called muscle hypertrophy. The opposite, atrophy, occurs when muscle mass decreases.

When training your horse, the aim is to support muscle development while avoiding excessive inflammation. Too much inflammation can cause swelling, heat, pain and reduced function. Prolonged or unresolved inflammation can also lead to unnecessary muscle cell damage.

Two types of muscle soreness

By pushing the limits and exerting strain on the muscles, muscle soreness and stiffness can occur. We can distinguish between two types of muscle soreness: early-onset muscle soreness and delayed-onset muscle soreness. Early-onset muscle soreness is a burning sensation in the muscles that occurs during or shortly after exertion. This muscle soreness is caused by an accumulation of lactic acid in the muscles, which stimulates the nerve endings and leads to pain.

Lactic acid is a byproduct that is produced when glucose (sugar) is converted into energy. This waste product is broken down in the liver. If more lactic acid is produced than the liver can break down, it accumulates in the muscles, causing the horse to experience acidosis. "Sobere" horse breeds have less blood per kilogram of body weight. As a result, these horses are more prone to acidosis during training. They are unable to transport sufficient oxygen to the muscles and remove waste products, leading to a faster accumulation in the muscles. 

If you want to increase activity in the second dressage test and improve your horse's endurance, here are some tips: 

• Always start with a proper warm-up. 
• Don't train for too long and incorporate interval training, where you have short bursts of intense exercise followed by periods of rest to allow the muscles to recover. 
• Start each day with Hartog Digest. This forage mix contains Diamond V yeast culture. The Diamond V yeast culture increases the hemoglobin level in the blood, enabling it to transport more oxygen and remove lactic acid from the muscles more efficiently. It supports the horse's heart rate, which will return to normal levels more quickly after training. 
• Always finish with a proper cooling-down routine. 

Prevent Overexertion 

Another form of muscle pain is delayed-onset muscle soreness. This type of muscle stiffness occurs 24 to 48 hours after you have demanded performance from your horse. The horse will feel stiff in the next training session. Micro-tears in the muscle cells are repaired with amino acids, which can be compared to the cement between building blocks. The cell wall becomes thicker and stronger, increasing its load-bearing capacity. Horses that are overtrained do not have enough time to recover and will not become stronger, but instead are more prone to injuries due to overexertion. 

The combination of POWERSTART® and Diamond V in Hartog Digest supports muscle tissue development, helping with stiffness. This forage mix has a positive effect on digestion and improves protein utilization by enhancing nitrogen fixation in gut bacteria. By stimulating cellulose-digesting bacteria and inhibiting the growth of undesirable bacteria, the yeast cultures promote better cellulose digestion. The volatile fatty acids released during cellulose digestion support endurance during performance. The combination of improved digestion and energy utilization on one hand, and reduced fatty acid mobilization during exercise on the other hand, results in lower lactic acid levels in the blood. This allows the horse to recover faster from exertion, injuries, and stress. 

5 tips to help muscles recover faster: 

• Provide the horse with at least 24 hours of rest (with movement) after intense exertion. 
• Ensure an adequate supply of drinking water and encourage water intake by adding Hartog Recovery herbal mash with additional electrolytes to their diet. 
• Always start with a warm-up, which promotes better blood flow and warms up the muscles. 
• Finish with a cooling-down period to allow the muscles to recover gradually. 
• Supply sufficient protein/amino acids to provide the building blocks necessary for muscle cell repair. 

For facts and evidence about the benefits of Diamond V yeast culture, visit diamondv.com. 

Want to learn more about Hartog Digest with its unique POWERSTART® formula? Check it out here! 

When to call the vet

Is your horse very stiff, reluctant to move, sweating or showing dark urine after exercise? Then it may be more than normal muscle soreness. Contact your veterinarian straight away.

Not sure whether your horse’s ration supports its training? Request free feeding advice.