My child has been diagnosed with low muscle tone. What does this mean?

Who gets a diagnosis of low muscle tone?

An infant or child will get a diagnosis of low muscle tone when:

  • The muscles appear to be less firm than usual
  • The child appears to be floppy and to have loose joints
  • The child appears to be less alert and have poor posture and attention

For a more technical discussion please see

FAQ'w.jpgThe difficulties experienced by children that lead to diagnosis of low muscle tone 

  • May be late learning to sit and walk - but not always
  • Have trouble sitting erect and working at a table - tend to sit with back rounded, may lean on one hand when drawing and writing
  • Have difficulty sitting still, tend to fidget, not complete school tasks
  • May tire very quickly, not like walking far, have trouble going up stairs
  • May be good at games that involve short bursts of running, but have difficulty with posture in sitting, drawing and handwriting - these tasks require sustained activity in the postural muscles
  • Sit between legs on floor (w-sitting), do not like cross legged sitting
  • Appear to have poor attention span or concentration, give up easily
  • Cannot hang on the monkey bars, do not like climbing on the jungle gym, are fearful

    It is important to note that all these difficulties are in fact related to a mixture of coordination problems, muscle tightness, weakness and poor endurance, generalised joint hypermobility, attention difficulties, a very cautious nature and avoidance of tasks that require effort and persistence.  

A careful assessment of all these issues will highlight which are contributing to the child's difficulties so that they can be addressed. 

What causes these difficulties? 

The most common cause of these difficulties is joint hypermobility  associated with a cautious temperament.

In individuals with hypermobile joints (loose or lax joints) the connective tissue structures that hold the body together have more give (are more easily stretched) than usual. This means that the muscles must work harder than usual to hold the keep a good posture and move. 

Joint hypermobility is probably the main  (and often unrecognized)  reason a child get a a diagnosis of low muscle tone. 

Children with a cautious temperament  are often quite anxious  which leads to avoidance of tasks that require effort and a tendency to give up very quickly. This in turn leads to low levels of activity, weakness and poor endurance. 

Read more here about the link between joint hypermobility and low tone 

Recognizing joint hypermobility

finger extension_0.jpg

Fingers that bend back to 90 degrees

wrist flexion_1.jpg

Wrist can be bent so that thumb touches the forearm 

hypermobile standing with elbows_0.jpg

Knees and elbows  bend backwards 

Hypermobile joints and tight muscles as a cause of movement difficulties

Sometimes joint hypermobility is missed because the child appears to have tight muscles. It is important to understand tight muscles is a common feature of joint hypermobility, especially in the muscles crossing the back and sides of the hips.  It is also important to understand that this muscle tightness if often an important underlying cause of some of the difficulties experienced by children with a diagnosis of low muscle tone. 

ben longsitting slumped.jpg w sitting.jpg sitting slumped hips abducted.jpg
Tight back and hip muscles affect sitting posture in children with joint hypermobility

What exactly is muscle tone?

The term muscle tone refers to two aspects of muscles structure and function.

  1. The inherent stiffness of a muscle - its resistance to being stretched and firmness when palpated (squeezed).
  2. A muscle's (or groups of muscles') readiness for action - the muscle's responsiveness to signals from the brain and to sensory feedback.

    The term low muscle tone is used when the muscles' stiffness is less than usual (ie it is low) and the readiness for action is also low (muscles respond slowly).

​How is a muscle's firmness (tone) tested?

The clinician makes a judgment about a muscles firmness and inherent stiffness by:

  • Squeezing the muscle to feel the resistance to compression
  • Lifting up and moving the limbs and feeling the resistance to this movement 

What determines a muscle's firmness? 

The firmness of a muscle is determined by its inherent stiffness and this in turn depends on the stiffness in the connective tissue sheaths that encase each muscle fiber, hold the bundles of muscle fibers together and connects the muscle to the tendons.

In children with hypermobile joints  the connective tissue is less stiff than usual. (It has more give and is more easily stretched).

This tendency for less stiff connective tissue which results in hypermobile (lax)  muscles and joints is genetically determined. About 10-15% of people are hypermobile.

The other very important structure that that determines a muscle's firmness and resistance to being stretched is the giant molecule titin. 

Titin is a very large elastic molecule found within the muscle cell.  The size and strength of the titin molecules is determined by the  amount of work a muscle is made to do on a regular basis. Strong muscles have larger and stiffer titin molecules - and this makes the muscle firmer and stiffer.  The muscle has better tone.

Generally speaking, strong muscles are firmer and have better tone.

Muscle tone, alertness and readiness for action

The term muscle tone is also used to describe the a muscle's readiness for actionThis is set by the child's alertness,  general level of arousal and readiness for action.  

The brain primes the muscles for action by sending signals to the muscles’ sensory receptors.  In effect the sensory receptors become more alert and provide more effective sensory feedback and respond more quickly. This allows for the rapid adjustments needed for maintaining balance and postural stability.

  • When a child is alert and engaged,  the muscles are primed for action.  The muscle tone is good and the posture is erect.
  • When a child is over-aroused, the muscles may become twitchy and overactive.  This makes the child less able to focus attention on a task.
  • If a child is anxious, finds a task difficult and is having trouble focusing his attention, the normal alertness for action signals do not reach the muscles. They become less responsive and provide less sensory feedback.  Muscle tone is lowered and the child's posture becomes less erect and alert..


Can low muscle tone (muscle laxity) be cured? The short answer is no.

The general stiffness of a child's muscles - which is what provides the muscles' tone, depends on two factors:

The stiffness in the connective tissue - this is genetically determines (it is in the DNA) and cannot be changed.  (See  Joint Hypermobility Syndrome)

The size of the titin molecules in the muscle cells. Stronger muscles have larger titin molecules. Stronger muscles have better tone.

Muscle and joint laxity cannot be "cured".  But, and this is important,  the movement difficulties  associated with muscle and joint laxity can be improved by  training

Task specific training has been shown to be the most effective approach to increase muscle strength, flexibility, endurance, coordination and attention.  

Task specific training means that you work on the aspects of posture and motor control that need improving.

This is because motor learning and fitness training are task specific: if you want to learn to ride a bicycle you need to get on a bicycle. And if you want to win a bicycle race you have to train on a bicycle. Swimming and running are simply no good.  

Find out more about helping your child improve motor skills using a task specific approach

To help the child: understand and address the causes DG webspace.jpg

Joint hypermobility syndrome – The connective tissue is more compliant than usual, leading to joint and muscle laxity and weak muscles

  • Intervention:  Exercises to improve strength and endurance and train posture and coordination. 

A cautious nature – The child avoids  tasks and activities that are difficult or require physical effort, which affects engagement and readiness for action.

  • Intervention: providing the child with tasks that challenge them in such a way that they become less avoidant and learn courage

Muscle weakness – as a result of lack adequate opportunities for engagement in activities that load the muscles in a way that leads to increased muscle strength

  • Intervention:   an exercise training programme that provides the child with appropriate challenges to learn new skills and engage in challenging tasks that load the muscles in a way that increases muscle strength.

Developmental coordination disorder where a child has difficulty learning new skills through experience and exploring ways to perform new and challenging tasks, leading to avoidance and lack of experience.

  • Intervention: a movement training program that provides the child with opportunities for learning new skills in a structured way and encourages participation in sporting and playground activities. 

Autism - is often associated with both joint hypermobility and DCD, along with anxiety and avoidance of challenging tasks.

DG Webspace Children_0.jpg

  • Intervention: task based intervention that provides opportunities for learning new skills and participation in playground and sporting activities

Down syndrome where joint hypermobility and muscle laxity is a defining feature.

  • Intervention: Strengthen, strengthen, strengthen and improve endurance and active participation 


Help your child: starting today

More about babies with joint hypermobility and associated low muscle tone

The TAMSKA 20-minutes-a-day challenge 



my 3 year old son

My 3 year old son has very low muscle tone his tendans are starting to bend in his legs . This came about when
He was 18 months old and woke up with a limp the 7 days later completely stopped walking he was then referred to
A neurologist he has had m.r.I scans they was normal . He has just recenetly had a chromes tests waiting on results from that he is very clumsy , very clingy , gets tired very easy and he is very behind compared to the children in his class
Hrs just had some special boots ordered to try and help with his walking as he is still very clumsy his spacial awareness us non existant all in all its a battle and still no closer to finding out what is wrong with him he's such a loving happy littleboy but it's just annoying after all this time and still no diagnosis . He also has asthma and really dry skin .

Tonsillectomy and low muscle tone/voice

Does anyone have feedback or experiences regarding the long term voice implications of having tonsils/adnoids removed for a child with low muscle tone? We have a six year old son with low muscle tone, with enlarged tonsils and moderate sleep apnea, and we're considering the procedure; but concerned about his voice. I understand his voice will most likely get higher/squeaky during the recovery period, but long term? It's an unknown of course, but welcome comments from anyone. Thank you.

My 5 year old has low muscle tone

My 5 year old us always running and moving fast. When she runs her right foot turns inward. She falls a lot due to this. We recently seen a physiotherapist who said my daughter has low muscle tone creating to much flexibility in her ankle,legs and lower abdomen. She has also been referred to get insoles for her shoes to correct her feet.

Is this a type of disability and can it be full corrected?

She has also being referred to occupation therapy as she seem to be struggling with class work and at a Lowe level than expected. She is also attending speech and therapy.

I was told that once all assessments have been completed then they would look and see if it's a type of Syndrome ore individual problems

Flexibility is caused by joint hypermobility


I think the first thing that needs to be clarified is that low muscle tone does not causeincreased  flexibility. Increased flexibility is caused by increased give in the connective tissues that hold the body together and gives it basic stability. This is called joint hypermobility.

Children with hypermobility benefit from a program of exercises to increase muscle strength and endurance. 

Joint hypernobility is often associated with other developmental disorders such as developmental coordination disorder / dypraxia, attention disorders, anxiety and specific language disorder.

The important thing to remember is that joint hypermobility is a separate issue. So while you are waiting for all the assessments to be completed find as much as you can about joint  hypermobility and ask your child's physiotherapist for exercises that you can do to get your daughter fitter. 


thickness difference

My one month old daughter has thickness difference in both the legs. Otherwise she is absolutly normal. Specialist told me that she had low tone in her legs. Can anyone suggest me what to di? I hv heard that this kind of pro lem may be resolved as baby starts walking. Is it true? Plz help me.

Ask the specialist to give you more information


It is not possible to provide any advise about the problems specific infants may have. You need to ask your doctor to clarify what she means when she says that your infant has low muscle tone in the legs and what you can expect in terms of development. 

Low muscle tone is a term that is used very loosely and most infants who seem to be a little floppy but are otherwise normal develop in the usual way but may be a little slow learning to crawl and walk. 


low toned muscles

My advice is not to gave up my daughter is 21 now! Walking, talking and learning everyday, she is immature and behind by about 10yr now but we are getting there at her speed!she's still in education and I hope she will until we get her to level 2 should she be 30 before this happens, there so many coarses now and even to pay for them in a further education college is a worthwhile expense! And repeating them if neccessary. I found music a great aid for her PT in her early days, a great distraction of what PT she was actually doing during the session!I hold the hit NO LIMITs responsible for her finally putting weight down her legs when she was popping away to it in a sitting postition on my knee, I tricked her slowly by edging up straight til she was in standing position! Firstly this lasted a mere 3or4 seconds but peservance and she's walking today, when they said she wouldn't! There is a way you just have to find it.

My son has lower tone in trunk


My son is 3 years old now. He had post birth hypoxia and diagnosed with Lower tone in trunk. Still he is not holding his head up, very floppy. He has been on NDT physiotherapy for one year.

Could you please suggest exercises?

19 month low muscle tone

Hi there my dd is 19 months and still not walking unassisted. We have been seeing a physiotherapist since she was 15 months, but it was only a month ago that she said our daughter has very low muscle tone in her legs/ankles, after feeling her feet. The main thing she had us do was encourage our daughter to walk with us holding her hands, and she went from never walking to walk, to asking to walk all the time.

My question is, if she has low muscle tone in her legs/ankles now, will she Always have low muscle tone, and have trouble jumping, running, climbing stairs etc?

She sat on time (at 6 months) but crawled very late --12 months and never showed interest in cruising, we basically had to play tricks for her to cruise along the couch but never does it on her own accord. She can stand up on her own, but she most often just sits back down after a second or two, and never takes a step.

We are seeing another set of specialists in a month-so hopefully that will reveal more.

But wondering in the meanwhile if there is something else we can do to help build her strength?

Thank you so much, this website has been very comforting so far.

19 month low muscle tone

You sound like you are describing my son (now 4). He took his first steps at 19 months old. He is diagnosed with GJH and Low Muscle tone. As a result he now has "knock knees" and dropped arches in his feet. He has been given special insoles in his shoes. He couldn't jump until he was 3.5 years old. Struggled with running and climbing stairs. But he got there in the end. He isn't quite as fast as running as his friends and is a little slower on the stairs. But does ok. It just took him a lot longer than average to reach certain milestones. We were advised by the physio to keep encouraging the physical activity and that seemed to help a lot. Not cured it but certainly helped.

Post new comment

By submitting this form, you accept the Mollom privacy policy.