Table 8. Between-day reliability for PF and RFD across maturity groups.
Category Variable Mean (± SD) ICC (95%CI) ICC
Interpretation		 CV (95%CI) SEM (95%CI)
All
PF 1898.93 ± 748.81 0.95 (0.92-0.97) Excellent 7.6 (6.6-8.6) 39.01 (35.11-42.91)
RFD50 3349.71 ± 2411.45 0.48 (0.32-0.64) Poor 39.3 (33.4-45.2) 1282.64 (1154.37-1410.90)
RFD100 3555.87 ± 2271.47 0.73 (0.62-0.83) Moderate 27.8 (23.6-32.0) 614.53 (553.08-675.99)
RFD150 3513.91 ± 2025.33 0.79 (0.71-0.87) Good 22.9 (19.5-26.4) 416.52 (374.87-458.17)
RFD200 3501.99 ± 1786.05 0.81 (0.75-0.89) Good 19.6 (16.3-22.8) 338.10 (304.29-371.92)
RFD250 3289.96 ± 1531.18 0.87 (0.82-0.93) Good 14.7 (12.4-17.1) 205.23 (184.71-225.75)
Pre
PF 1090.21 ± 217.51 0.83 (0.74-0.95) Good 7.4 (5.4-9.3) 36.65 (32.98-40.31)
RFD50 2018.94 ± 1182.92 0.30 (0.01-0.65) Poor 40.5 (29.9-51.0) 840.63 (756.57-924.70)
RFD100 2075.73 ± 897.65 0.43 (0.13-0.73) Poor 29.1 (20.1-38.0) 509.49 (458.54-560.44)
RFD150 1964.72 ± 690.06 0.43 (0.11-0.72) Poor 24.5 (17.5-31.5) 394.03 (354.63-433.44)
RFD200 1937.56 ± 541.45 0.49 (0.20-0.77) Poor 19.6 (14.8-24.4) 278.30 (250.47-306.13)
RFD250 1825.43 ± 454.49 0.60 (0.35-0.84) Moderate 15.2 (11.5-18.9) 183.60 (165.24-201.96)
Circa
PF 1896.76 ± 468.78 0.84 (0.73-0.94) Good 8.3 (6.4-10.1) 75.20 (67.68-82.72)
RFD50 3531.81 ± 2298.92 0.09 (0.00-0.43) Poor 43.9 (31.9-56.0) 2149.94 (1934.94-2364.93)
RFD100 3595.28 ± 1679.46 0.31 (0.06-0.62) Poor 31.4 (23.7-39.0) 1174.87 (1057.38-1292.36)
RFD150 3499.47 ± 1427.77 0.42 (0.20-0.72) Poor 25.2 (18.8-31.6) 837.06 (753.35-920.76)
RFD200 3443.47 ± 1191.70 0.41 (0.24-0.75) Poor 22.9 (16.7-29.1) 732.96 (659.67-806.26)
RFD250 3217.58 ± 916.29 0.59 (0.49-0.86) Moderate 16.0 (11.5-20.5) 384.93 (346.43-423.42)
Post
PF 2697.34 ± 434.40 0.79 (0.58-0.91) Good 6.8 (5.0-8.5) 91.08 (81.97-100.18)
RFD50 4705.24 ± 2809.73 0.64 (0.37-0.84) Moderate 31.8 (23.1-40.5) 990.20 (891.18-1089.22)
RFD100 5281.42 ± 2769.23 0.80 (0.60-0.91) Good 20.9 (14.8-27.1) 538.44 (484.59-592.28)
RFD150 5270.82 ± 2181.26 0.82 (0.63-0.92) Good 17.3 (12.1-22.6) 388.80 (349.92-427.68)
RFD200 5250.79 ± 1619.35 0.77 (0.56-0.90) Good 14.3 (8.4-20.1) 361.57 (325.41-397.73)
RFD250 4922.64 ± 1195.04 0.71 (0.47-0.88) Moderate 11.4 (7.0-15.9) 340.80 (306.72-374.88)
PF = peak force; RFD = rate of force development; SD = standard deviation; ICC = intraclass correlation coefficient; CI = confidence interval; CV = coefficient of variation; SEM = standard error of measurement; Pre = pre-PHV; Circa = circa-PHV; Post = post-PHV; PHV = peak height velocity.