Low Muscle Tone | What Does Hypotonia Mean?

In the pediatric therapy world, a diagnosis of “low tone” or “hypotonia” is often given. But what exactly does this diagnosis mean? Muscle tone is the term for the resting length of muscles in the body ( i.e. before a contraction). With low muscle tone, the resting length of the muscles is greater than average and causes hyperextension at the joints, or what some refer to as “double jointedness.” (However, the term double jointed is misleading, as a person doesn’t actually have two joints, just increased muscle length and therefore increased flexibility at the joint).

Signs of Hypotonia in Children:

How can you tell if you or your child has low muscle tone? As stated above, individuals with low tone muscles often have increased flexibility at many joints. The muscles may feel soft and squishy, and because they have increased resting length it literally takes longer for the muscles to contract. Therefore, the individual may seem slow to get going or even lazy, but there truly may be a physiological reason behind it.

Also, because it requires more energy to get the muscles moving, these individuals may be reluctant to move, or conversely, they may move more because sitting still is exhausting and uncomfortable.

Other difficulties you might notice in an individual with low muscle tone include:

• Poor posture

• Poor coordination

• Poor balance

• Poor body awareness

You might not believe it from the above description, but several athletes actually have low muscle tone – Michael Phelps, Michael Jordan and many Olympic gymnasts, to name a few! Increased flexibility at some joints is actually helpful for performing some athletic events.

Hypotonia Solutions:

What can be done about low muscle tone? Outside of neurological events (like a traumatic brain injury or seizure) the actual length of the muscle at rest cannot be changed. However, strengthening the muscles around the joint increases stability and the number of muscle fibers, which will decrease the effects of low muscle tone over time. Pediatric occupational and physical therapists are trained to recognize low muscle tone and treat the negative effects in a fun and motivating way for children.