Hand grip strength

• A directly measured value. A strain gauge in the handle converts the squeeze into kilograms; nothing is derived from impedance.
• Two attempts per hand are usually taken and the best one is recorded, with rest in between.
• HGS/WT is the measured force divided by body weight, expressed as a percentage.
• On the InBody 970S result sheet grip strength is printed among the sarcopenia parameters next to the skeletal muscle index, because the two are read together.

• Read both hands separately and watch the difference. The dominant hand tends to be somewhat stronger; a large or newly appeared difference matters more than the absolute numbers.
• The threshold printed among the sarcopenia parameters follows the low-strength cut-off of the European EWGSOP2 consensus — 27 kg for men and 16 kg for women. It is not a health threshold or a diagnosis, it is a prompt for further assessment.
• Always read HGS/WT together with the force in kilograms. On its own it moves whenever body weight moves, even at unchanged strength.
• A single measurement does not describe your strength, only one attempt. A bad day, a sore hand or a tired forearm after training will pull it down.

• Follow strength over weeks to months. Day to day it varies with fatigue and execution more than actual muscle change.
• Rising strength at stable muscle mass is common and makes sense — the nervous system learns to recruit muscle fully before tissue is added.
• Falling strength at preserved muscle mass deserves attention: the amount of muscle held, its function did not.
• During weight loss, keeping strength is a better sign than keeping weight. If strength and muscle mass fall together, the pace is too fast or protein and resistance training are missing.

General principles: how to read change between measurements →

• Skeletal muscle index (SMI) – muscle amount relative to height; strength and amount are judged together.
• Skeletal muscle mass – the absolute amount of muscle that grip complements functionally.
• Segmental lean mass – shows whether a difference between hands matches a difference in tissue.
• Phase angle – another indicator tied to cell state that often tracks with strength.
• Weight – it enters the HGS/WT ratio, so its change moves that ratio too.

• A strong grip does not mean a lot of muscle and a weak grip does not mean a lack of it. Amount and function are related but not the same.
• This is not a forearm test. Grip stands in for overall muscle strength, so training the grip itself moves the result only partly.
• A value below the printed threshold is not a diagnosis of sarcopenia. The criteria require confirmation by muscle quantity and quality, and severity is judged by physical performance.
• Numbers from a different dynamometer are not comparable. A different handle design and calibration give a different result.

• Handle span setting and the position of hand, elbow and wrist. Identical execution is the precondition for comparability.
• Instruction and encouragement from the operator; motivation shows up measurably in a maximal attempt.
• Fatigue after resistance training, especially exercises loading the grip.
• Hand pain, arthritis, a recent injury or a state after wrist surgery.
• Time of day and general fatigue; morning and evening need not match.
• Wet or greasy hands that worsen contact with the handle.

• Always measure the same way: same handle setting, same position, same number of attempts. Without that the trend cannot be read.
• Record both hands separately and follow their difference, not just the better result.
• To increase strength, focus on whole-body resistance training and sufficient protein. Squeezing a grip ring alone mostly trains the grip itself.
• Falling strength together with fatigue, unintended weight loss or worsening walking belongs with a doctor, not with another measurement.

• It does not measure the amount of muscle. It is the functional performance of one squeeze, not a bioimpedance estimate of muscle tissue.
• It does not diagnose sarcopenia or any other condition. The criteria always assess muscle strength alongside other indicators; the dynamometer number is one input.
• The result depends strongly on execution: handle span, elbow and wrist position, duration of the squeeze, the operator instruction and momentary motivation. Even two attempts of the same hand differ.
• Hand pain, arthritis, a recent injury, a state after wrist surgery, a callus or fatigue after resistance training lower the value without any change in the muscles.
• The manufacturer documentation available to us states no reference range for grip strength. The threshold on the result sheet comes from sarcopenia consensus, not from device validation.
• Values from a different dynamometer are not interchangeable. Devices differ in handle design and calibration.
• The strength-to-weight ratio changes even when strength does not and only weight moves. Always read it together with the force in kilograms.