Tendons play a fundamental role in athletic performance, especially in activities that require speed, jumping, and explosiveness. However, for many trainers and physiotherapists, the focus on tendon training and its importance in injury prevention is not always clear. In this conversation with Keith Baar, a researcher specializing in muscle and connective tissue physiology, we explore the science behind tendon training and its practical applications in athlete performance and rehabilitation.

The Importance of Stiffness and Elasticity in Connective Tissues

Unlike ligaments, tendons require a balance between stiffness and elasticity. Excessive stiffness in a tendon can increase the risk of muscle injuries, especially in sports that demand high levels of explosiveness and speed. Baar explains that tendons need to be elastic enough to allow the muscle to generate power without creating excessive tension that could lead to injury, such as a non-contact muscle tear.

In the case of ligaments, stiffness is essential to provide joint stability. For example, a knee ligament must be stiff to prevent unwanted movements that could compromise the joint. On the other hand, for tendons, a moderate level of elasticity allows the force generated by the muscle to be transferred efficiently to movement without placing too much stress on the tendon structure.

Training Tendon Stiffness to Improve Performance

To maximize performance, it is essential to adjust tendon stiffness according to the type of athlete and sport. Baar points out that endurance athletes, such as long-distance runners, require less rigid tendons, while sprinters or athletes in contact sports, like football, need a higher level of tendon stiffness to enhance their rate of force development.

Eccentric training is crucial for increasing tendon stiffness in a controlled manner, allowing the tendon to adapt to high loads without overloading the muscle. This is particularly useful for athletes who need to withstand explosive loads, such as jumpers and sprinters.

The Relationship Between Stiff Tendons and Muscle Injuries

One of the challenges in tendon training is avoiding the risk of muscle injuries. When a tendon is too stiff relative to muscle strength, the risk of muscle tears increases. Baar explains that this balance is particularly important in high-intensity sports, where a fast, explosive movement can cause excessive muscle stretching if the tendon is too rigid.

The solution lies in adjusting tendon stiffness based on the specific demands of the sport and the athlete’s strength level. This can be achieved through a combination of resistance training, eccentric exercises, and, in some cases, isometrics.

The Science of Tendon Adaptation: Isometric Training and Stress Relaxation

Isometric training is a powerful tool for tendon adaptation, especially in rehabilitation. Through prolonged isometric exercises, a process known as stress relaxation can be induced, where the strongest parts of the tendon adapt, allowing for a controlled reduction in tendon tension. Baar recommends holding isometric contractions for at least 30 seconds to achieve the best results for tendon adaptation.

For athletes with existing tendon injuries, isometric training is even more important. This type of training allows the injured area of the tendon to receive a sustained and controlled load, promoting targeted regeneration and strengthening of the tendon tissue in that area.

Example Exercises to Strengthen Tendons and Enhance Performance

1. Isometric Leg Extension Exercises: This classic exercise is performed on a leg extension machine, where the athlete holds the position at a 70-degree knee flexion and pushes without completing a full movement. This exercise enhances tendon stiffness without placing excessive strain on the muscle.
2. Isometric Squats at Extended Muscle Length: Squats performed in a position of maximum muscle length allow for safe tendon loading and help reduce the risk of muscle tears. This position facilitates greater elasticity in the muscle and tendon system.
3. Slow Eccentric Load Movements: Performing slow eccentric exercises, such as heavy lifts at a controlled speed, allows collagen fibers in the tendon to slide, which reduces overall stiffness and decreases the risk of injuries.

Nutrition and Its Role in Tendon Health

Nutrition also plays a crucial role in tendon recovery and strengthening. Baar highlights that consuming hydrolyzed collagen before training can help stimulate collagen synthesis in tendons, promoting recovery and strengthening. However, it’s important to avoid consuming caffeine along with collagen, as recent studies indicate that caffeine may inhibit collagen synthesis, reducing its effectiveness.

Tendon Rehabilitation: A Holistic Approach

For athletes recovering from a tendon injury, the rehabilitation process should focus on a holistic approach that combines nutrition, isometric training, and progressive loading on the tendon. Baar suggests a dual daily session strategy, where one session focuses on the protection and strengthening of connective tissues, while the other focuses on general physical conditioning, such as cardiovascular and strength training.

Conclusion: Tendon Training for Optimal Performance and Injury Prevention

Tendon training is an essential component for enhancing performance and preventing injuries in high-level athletes. Adapting tendon stiffness and elasticity to the individual needs of each athlete and sport is key to optimizing their load-bearing capacity and avoiding injuries.

For trainers and physiotherapists, it is essential to understand how to adjust these parameters through specific exercises, both isometric and eccentric, and complement training with adequate nutrition. With this approach, it is possible to maximize performance and prolong the athletic career of athletes, reducing the risk of tendon injuries and improving their capacity for recovery