By: Melissa Baudo Marchetti, PT, DPT, SCS, MTC with One on One Physical Therapy

Do you have multiple or recurring injuries that seem to not go away? The most common sites of overuse injuries in triathletes are tendon injuries and muscles strains in the knee (25%), lower leg (23%), and lower back (23%)1. Injuries can happen because you are training way too much, you are not preparing or recovering properly, or because you have weaknesses or “weak links” in your kinetic chain. Triathletes can develop weak links and imbalances in flexibility, strength and range of motion, which can adversely affect performance.

Someone may have taught you the fundamentals of running, swimming, and cycling, but perhaps no one ever taught you that in order to prevent injuries and perform at your best, it is critical that your body is functioning optimally. Assessing and correcting the muscular asymmetries in your kinetic chain may reduce the risk of sport related injuries.

Once an injury or pain occurs and if not treated or insufficiently addressed, weaknesses or “weak links” can persist within the athlete’s kinetic chain. The kinetic chain is a combination of successively arranged joints that create a coordinated movement2. For example, when you are running, your feet absorb and transfer force through your knees into your hips and spine to propel you forward. Remember that song, “your hip bone is connected to your knee bone, the knee bone is connected to your ankle bone.” Well, it’s true! The best way to maximize power and minimize load to your muscles and joints is through efficient use of your kinetic chain3.

It is common that injuries or pain that you are dealing with may be a result of deficits along the kinetic chain that may be above or below the actual location of your pain or injury. For example, your knee pain may be a result of weak links in your gluteal muscles at your hip. As a runner, if your gluteal muscles are weak, this may cause your knee to collapse inward placing abnormal forces on your knees. If you experience shoulder pain while you swim, there may be weak links in either your scapular stabilizers (muscles around your shoulder blade) or your pelvic stabilizers (muscles in your hips and core) causing you to overuse your rotator cuff muscles. In order to generate the same amount of force if you have a weak link in your core or pelvis, you will overuse some other part of the body, often the low back, hips, shoulders, or Achilles causing strains and tendinitis. So, while you may feel strong, you may have some hidden weak links in your musculoskeletal system that are actually limiting you and may be the source of your pain.

So, how do we assess for weak links? Neurac Weak Link Testing is a comprehensive, research-based method utilizing the Redcord Suspension Workstation for the examination and treatment of neuromuscular weak links and asymmetries. Redcord is unique because you exercise while suspended in ropes and bungee cords, which facilitates muscle activation and allows you to exercise pain-free. Studies have shown that injury, pain and inactivity disturb our brain’s capacity to switch on the right muscles at the right time and with the right amount of strength4. This loss of function diminishes our “local” muscle control, often leading to decreased quality of movement and increased pain causing our larger “global” muscles to take over (compensate) and eventually become stressed, strained and painful5,6,7. For example, when you injure your back, the smaller, deeper muscles of the spine that connect your vertebra will often shut down and the larger, long muscles of your back (the paraspinals) will overcompensate, which makes your back feel tight, stiff, and sore. Does your back ever feel like this? The Neurac Method aims to normalize this muscle interaction by re-activating your muscles. By using the Redcord you will experience decreases in pain and stiffness, increase in strength, and improved function in less time than conventional treatment methods.

Right Pelvic Lift Strong

Left Pelvic Lift Weak Link

You can see in the video that the left hip is weaker and the athlete cannot maintain normal height or alignment in the hips and pelvis when performing the test. There is also a lot of movement in the ropes and his body shifts to the right as he tries to engage his left hip muscles, which are signs of a weak link.

Right Hip Abduction Strong View 1

Left Hip Abduction Weak Link View 1

Here you can see the weak link in the left hip, as he cannot fully engage the hip muscles in order to achieve optimal height in the test position.

Right Hip Abduction Strong View 2

Left Hip Abduction Weak Link View 2

Here you can see that there is a lot of movement on the left side as he performs the test in the ropes when compared to the right. Weak links like these can cause hip and low back pain.

Physical Therapists with knowledge of the sport you play can assess and correct weaknesses in the kinetic chain in order to treat pain and injuries, prevent future injuries, and enhance your performance lengthening your sports career. Weak Link Testing should be a component of a physical therapy evaluation of any triathlete. If you are having knee, hip, shoulder, neck or back pain, or simply want to improve your flexibility, joint and spinal mobility, and just perform better, contact your Physical Therapist to help get you back in the race.

This article was submitted by Melissa Baudo Marchetti PT, DPT, SCS, MTC. She received her Doctor of Physical Therapy from Emory University and is a Board Certified Sports Clinical Specialist at One on One Physical Therapy, a multidisciplinary private practice in Atlanta, GA. She teaches a Sports Physical Therapy Course and assists in teaching Orthopedics within the Division of Physical Therapy at Emory University. Marchetti’s email address is and more information can be found at


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