Diagnostics
Assessing muscle mass and body composition with BIA
Getting up from a low armchair is becoming harder. You need more frequent breaks on the stairs, although your weight has hardly changed. When changes like these occur, it is worth looking more closely at your muscles. Particularly with osteoporosis, the interaction of bones, muscle strength and safe movement matters.
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Understanding
A closer look
At OrthoCoast in Wolgast, we can assess body composition using the seca mBCA 555. Bioelectrical impedance analysis, or BIA, complements the medical examination, strength measurements and functional tests. Together, this information helps assess possible muscle loss and discuss useful next steps.
What BIA can tell us about your body
Body weight alone tells us little about how much muscle, fat and water it comprises. Their proportions can change even when weight stays the same. BIA measures the body's electrical behaviour using a very weak alternating current. From this, the analysis software calculates estimates of skeletal muscle mass, fat mass and body water, among other values.
Skeletal muscles enable voluntary movements, such as walking or standing up. Their amount is therefore an important part of assessment. However, BIA does not image muscles like an MRI and does not measure muscle strength. Its values are considered together with suitable reference values and your personal situation.
Why bones and muscles are considered together
In osteoporosis, bone strength is reduced. At the same time, how safely you stand and walk, or whether you fall, plays an important role in fracture risk. Weakening muscles can make this situation more difficult.
When low bone density or osteoporosis and sarcopenia occur together, this is called osteosarcopenia. Sarcopenia is a muscle condition in which strength in particular declines, together with reduced muscle quantity or quality. Not every feeling of fatigue or single low measurement means this condition is present. We bring the findings together to clarify whether there are signs of muscle loss that needs treatment.
Further information
Muscle quantity and muscle strength answer different questions
BIA can add information about how much muscle is present. A strength measurement, by contrast, shows the force you can actually generate. In a handgrip strength test, for example, you squeeze a measuring device. Repeatedly standing up from a chair, known as the chair-rise test, helps assess the legs' performance during an everyday movement.
The results complement each other. Greater muscle mass does not automatically mean greater strength. Conversely, difficulty standing up may also be partly caused by pain or a joint problem. We therefore consider measurements together with the physical examination and your everyday observations. This allows a better assessment of your muscles' functional performance than a single value.
What the phase angle can additionally show
The phase angle is an electrical measurement from BIA. It is influenced, among other things, by cell membrane properties and the distribution of body water. In the right context, it can add information about tissue and nutritional status and be helpful for monitoring changes.
It is not, however, a stand-alone test that assesses overall muscle quality or your health. Age, sex, illness and fluid balance influence its interpretation. A low value alone proves neither malnutrition nor sarcopenia. What matters is whether it fits the other findings and what consequence follows for you.
How the measurement complements osteoporosis assessment
DXA bone density scanning primarily answers the question of bone density. BIA adds information about body composition. The two examinations have different roles and do not replace each other.
In the combined assessment, we look at muscle quantity, the strength actually available and everyday function. Questions about nutrition, weight changes and fluid balance are also included. Whether you have unintentionally lost weight or become much less active after a prolonged illness, for example, may matter for interpretation. Which measurements and tests are useful depends on your question and physical capacity. There is no need for a fixed examination programme that everyone must complete in full.
What the results may mean for your treatment
The examination aims to help prepare a specific decision. If muscle loss and low strength occur together, adapted strength training, falls prevention measures and a review of nutrition may become important topics. Marked weight loss or further symptoms may require additional medical assessment.
We assess with you which everyday goals appear achievable and how change can be judged. This might mean getting up more easily, walking with greater confidence or improving physical capacity. Follow-up measurements can accompany this progress. However, a changed BIA value alone does not prove training success: shifts in body water can also change measurements. Osteoporosis treatment remains guided by your fracture risk independently of this.
How a BIA measurement works
For the measurement, you stand barefoot on the measuring platform and hold the designated hand contacts. Our team helps you find the correct position. The measurement itself takes only a short time; preparation and medical interpretation form part of the whole examination. No X-rays are used.
For follow-up results to be comparable, measurement conditions should be as similar as possible. Please therefore tell us about marked weight changes, fluid retention and current illnesses. We agree specific preparation instructions with you before the appointment. You do not need to change your fluid intake or prescribed medicines yourself.
For comparable results, come as rested as possible and, for follow-up measurements, at a similar time of day. Empty your bladder before measurement, ideally immediately after arriving at our practice. An appointment before a meal or a few hours afterwards is preferable. Please avoid drinking large amounts immediately before measurement. Avoid alcohol during the preceding twelve hours and intensive training on the previous day and immediately before the appointment. Do not change medically prescribed fluid intake or medication on your own. If a condition means you need to eat or drink regularly, we will agree the preparation with you.
When particular checks are needed before the examination
Bioimpedance measurement with this device must not be performed in people with electronic implants, such as a pacemaker, or active prostheses. Connected electronic medical devices may also rule out measurement. Tell us beforehand about such devices, as well as heart rhythm disorders or pregnancy.
For this measurement, you must be able to stand safely enough in an upright position and reach the hand and foot contacts. If this is not possible, we will discuss another way of assessing you. Simple weight measurement must be distinguished from bioimpedance measurement.
What matters for your decision
Discuss costs and the next step
If you notice changes in strength, unsteady walking or have questions about your muscles in relation to osteoporosis, mention this when arranging your appointment. We clarify which examination suits your situation and what BIA can contribute.
We discuss the scope of the service and costs before the examination. If you are covered by German statutory health insurance and wish to pay yourself for a service that is not covered, you receive a cost estimate in advance. The service is provided only after your written confirmation of your wish for treatment and acceptance of the costs. The name of the examination does not imply a general guarantee of reimbursement.
Frequently asked questions
Can BIA identify osteoporosis?
BIA does not measure bone density. It adds to assessment of muscle mass and body composition. For osteoporosis assessment in terms of estimating fracture risk, medical history, physical examination, laboratory parameters and, where appropriate, a DXA scan are considered together, among other information.
Do I automatically have sarcopenia if my muscle mass is low?
Low muscle quantity is a finding that needs interpretation. Assessment includes muscle strength in particular and, where appropriate, further functional tests. The diagnosis is not simply read from the BIA analysis alone.
Is an examination useful even at a normal weight?
Yes, if there is a specific medical question. A normal weight does not rule out low muscle mass. Whether the measurement is helpful for you depends on symptoms, risks and the possible consequences.
Does the phase angle measure the quality of my muscles?
It can add to the assessment, but does not describe muscle quality on its own. Strength, function, body composition and clinical findings must be considered together.
Can changes from training be monitored?
Under comparable measurement conditions, repeated examinations can provide indications of changes in body composition. Strength measurements, function and your everyday life additionally show whether you benefit from the agreed measures.
What should I do if I cannot stand safely on the measuring platform?
Tell us before the examination. We will assess whether it can be performed safely and discuss other suitable examinations if necessary. BIA is not a prerequisite for a medical assessment of your symptoms.
Your next step
