Validity of a portable hanging scale to assess the isometric muscle strength during knee movement

Validity and Test-Retest Reliability of a Novel Push Low-Cost Hand-Held Dynamometer for Knee Strength Assessment During Different Force Ranges

“…A convenience sample of 19 participants (24.21±4.06 years; 1.70±0.07 m; 67.83±14.03 kg) were recruited by the public invitation through folders and personal contacts. The a priori two-tailed point biserial model sample size calculation was performed using the Gpower 3.1 Software (Franz Faul, Univesity Kiel, Germany) considering a coefficient of determination of 0.97 with an effect size of 1.04 obtained from a previous similar study [18], with an alpha of 5% and a sampling power (1-β) of 95%. A sample size of 15 subjects was returned with an actual power of 0.962.…”

“…Inexpensive, accurate and more affordable devices are then essential to objectively assess isometric muscle strength [16]. Thus, hanging scales, load-cell transducers and hand-held dynamometers (HHD) have been proposed as valid and reliable alternatives [7,[17][18][19][20]. Despite their usefulness, portability and the efforts to ensure the relative accu-rate measures obtained from those devices, most previous studies only described the overall tension or compression force outputs applied on the equipment, not distinguishing the acquired precision during different ranges of load [7,[17][18][19].…”

“…Thus, hanging scales, load-cell transducers and hand-held dynamometers (HHD) have been proposed as valid and reliable alternatives [7,[17][18][19][20]. Despite their usefulness, portability and the efforts to ensure the relative accu-rate measures obtained from those devices, most previous studies only described the overall tension or compression force outputs applied on the equipment, not distinguishing the acquired precision during different ranges of load [7,[17][18][19]. The lack of precision from those measurements may lead to misinterpretation during softer compared to heavier loads applied on the device (i.e., accuracy to differentiate weak vs. strong/normal muscles).…”

Validity and Test-Retest Reliability of a Novel Push Low-Cost Hand-Held Dynamometer for Knee Strength Assessment during Different Force Ranges

“…Inexpensive, accurate and more affordable devices are then essential to objectively assess isometric muscle strength [ 16 ]. Thus, hanging scales, load-cell transducers and hand-held dynamometers (HHD) have been proposed as valid and reliable alternatives [ 7 , 17 , 18 , 19 , 20 ]. Despite their usefulness, portability and the efforts to ensure the relative accurate measures obtained from those devices, most previous studies only described the overall tension or compression force outputs applied on the equipment, not distinguishing the acquired precision during different ranges of load [ 7 , 17 , 18 , 19 ].…”

“…Thus, hanging scales, load-cell transducers and hand-held dynamometers (HHD) have been proposed as valid and reliable alternatives [ 7 , 17 , 18 , 19 , 20 ]. Despite their usefulness, portability and the efforts to ensure the relative accurate measures obtained from those devices, most previous studies only described the overall tension or compression force outputs applied on the equipment, not distinguishing the acquired precision during different ranges of load [ 7 , 17 , 18 , 19 ]. The lack of precision from those measurements may lead to misinterpretation during softer compared to heavier loads applied on the device (i.e., accuracy to differentiate weak vs. strong/normal muscles).…”