Twelve female division I collegiate volleyball players were recruited to examine the reliability of several methods for calculating the rate of force development (RFD) during the isometric midthigh clean pull. All subjects were familiarized with the isometric midthigh clean pull and participated in regular strength training. Two isometric midthigh clean pulls were performed with 2 minutes rest between each trail. All measures were performed in a custom isometric testing device that included a step-wise adjustable bar and a force plate for measuring ground reaction forces. The RFD during predetermined time zone bands (0-30, 0-50, 0-90, 0-100, 0-150, 0-200, and 0-250 milliseconds) was then calculated by dividing the force at the end of the band by the band's time interval. The peak RFD was then calculated with the use of 2, 5, 10, 20, 30, and 50 milliseconds sampling windows. The average RFD (avgRFD) was calculated by dividing the peak force (PF) by the time to achieve PF. All data were analyzed with the use of intraclass correlation alpha (ICCα) and the coefficient of variation (CV) and 90% confidence intervals. All predetermined RFD time bands were deemed reliable based on an ICCα >0.95 and a CV <4%. Conversely, the avgRFD failed to meet the reliability standards set for this study. Overall, the method used to assess the RFD during an isometric midthigh clean pull impacts the reliability of the measure and predetermined RFD time bands should be used to quantify the RFD.

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Introduction/Aims Although electromyography remains the “gold standard” for assessing and diagnosing peripheral nerve disorders, ultrasound has emerged as a useful adjunct, providing valuable anatomic information. The objective of this study was to conduct a systematic review and meta‐analysis evaluating the normative sonographic values for adult peripheral nerve cross‐sectional area (CSA). Methods Medline and Cochrane Library databases were systematically searched for healthy adult peripheral nerve CSA, excluding the median and ulnar nerves. Data were meta‐analyzed, using a random‐effects model, to calculate the mean nerve CSA and its 95% confidence interval (CI) for each nerve at a specific anatomical location (= group). Results Thirty groups were identified and meta‐analyzed, which comprised 16 from the upper extremity and 15 from the lower extremity. The tibial nerve (n = 2916 nerves) was reported most commonly, followed by the common fibular nerve (n = 2580 nerves) and the radial nerve (n = 2326 nerves). Means and 95% confidence interval (CIs) of nerve CSA for the largest number of combined nerves were: radial nerve assessed at the spiral groove (n = 1810; mean, 5.14 mm2; 95% CI, 4.33 to 5.96); common fibular nerve assessed at the fibular head (n = 1460; mean, 10.18 mm2; 95% CI, 8.91 to 11.45); and common fibular nerve assessed at the popliteal fossa (n = 1120; mean, 12.90 mm2; 95% CI, 9.12 to 16.68). Publication bias was suspected, but its influence on the results was minimal. Discussion Two hundred thirty mean CSAs from 15 857 adult nerves are included in the meta‐analysis. These are further categorized into 30 groups, based on anatomical location, providing a comprehensive reference for the clinician and researcher investigating adult peripheral nerve anatomy.

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