Hematocrit concentrations were analyzed in duplicate in whole blood using microcapillary and microcentrifugation (CritSpin, Westwood, MA, USA) techniques. Whole blood hemoglobin was analyzed in duplicate using an automated analyzer (HemoCue, Cypress, CA, USA). Plasma volume shifts were calculated using the formula established by Dill and Costill (
1974). The coefficient of variation for hematocrit was 0.87% and was 0.65% for hemoglobin.
Serum concentrations of
testosterone, cortisol, and myoglobin and plasma concentrations of BDNF, IL‐6 (High Sensitivity), and CRP, were obtained via commercially available enzyme‐linked immunosorbent assay (
testosterone, cortisol, myoglobin: Calbiotech, Spring Valley, CA, USA; BDNF, High‐Sensitivity IL‐6, CRP: R&D Systems, Minneapolis, MN, USA) per manufacturer's instructions. All samples for a particular assay were thawed once and analyzed in duplicate by the same technician using a BioTek
Eon spectrophotometer (BioTek Instruments, Inc., Winooski, VT, USA). Intra‐assay coefficients of variation for each assay were: 8.15% for
testosterone; 9.21% for cortisol; 7.52% for myoglobin; 7.57% for BDNF; 5.50% for IL‐6; 3.36% for CRP. Interplate coefficients of variation for each assay were: 12.77% for
testosterone; 4.85% for cortisol; 15.10% for myoglobin; 17.96% for BDNF; 5.92% for IL‐6; 6.03% for CRP.
Varanoske A.N., Wells A.J., Kozlowski G.J., Gepner Y., Frosti C.L., Boffey D., Coker N.A., Harat I, & Hoffman J.R. (2018). Effects of β‐alanine supplementation on physical performance, cognition, endocrine function, and inflammation during a 24 h simulated military operation. Physiological Reports, 6(24), e13938.
