Table 1.
Estimates of the proportion of fiber types in muscle obtained by resampling 25, 50, or 100 of the phenotyped muscle fibers using ordered (Ordered) and random (Random) selection of phenotyped muscle fibers for each subject.
| Fiber Type | Ordered | Random | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Fiber Count | Fiber Count | |||||||||
| 25 | 50 | 100 | P | 25 | 50 | 100 | P | |||
| S1 | I |
0.48 (0.40, 0.56) |
0.46 (0.42, 0.68) |
0.59 (0.56, 0.63) |
< 0.0001 |
0.56 (0.52, 0.64) |
0.56 (0.52, 0.62) |
0.57 (0.54, 0.60) |
0.67 | |
| I/IIa | N/A |
0.06 (0.04, 0.08) |
0.05 (0.04, 0.06) |
< 0.0001 |
0.04 (0.04, 0.08) |
0.06 (0.04, 0.08) |
0.06 (0.05, 0.08) |
< 0.05 | ||
| IIa |
0.52 (0.44, 0.60) |
0.48 (0.44, 0.52) |
0.34 (0.30. 0.37) |
< 0.0001 |
0.36 (0.28, 0.40) |
0.34 (0.29, 0.38) |
0.34 (0.31, 0.37) |
0.42 | ||
| IIa/IIx | N/A | N/A |
0.02 (0.01, 0.03) |
< 0.0001 |
0.04 (0.00, 0.04) |
0.02 (0.02, 0.04) |
0.03 (0.02, 0.04) |
< 0.0001 | ||
| IIx | N/A | N/A | N/A | - | N/A | N/A | N/A | - | ||
| S2 | I |
0.32 (0.24, 40) |
0.28 (0.24, 0.32) |
0.28 (0.25, 0.31) |
< 0.0001 |
0.24 (0.16, 0.28) |
0.22 (0.18, 0.28) |
0.23 (0.20, 0.26) |
0.74 | |
| I/IIa |
0.28 (0.20, 0.36) |
0.20 (0.16, 0.24) |
0.20 (0.17, 0.22) |
< 0.0001 |
0.24 (0.20, 0.28) |
0.24 (0.20, 0.28) |
0.24 (0.21, 0.27) |
0.15 | ||
| IIa |
0.04 (0.00, 0.04) |
0.04 (0.02, 0.06) |
0.04 (0.03, 0.05) |
< 0.01 |
0.12 (0.08, 0.16) |
0.12 (0.08, 0.14) |
0.11 (0.09. 0.13) |
0.14 | ||
| IIa/IIx |
0.04 (0.00, 0.08) |
0.18 (0.14, 0.22) |
0.18 (0.15,0.20) |
< 0.0001 |
0.16 (0.12, 0.20) |
0.14 (0.12, 0.18) |
0.15 (0.12, 0.17) |
0.95 | ||
| IIx | N/A | N/A | N/A | - | N/A | N/A | N/A | - | ||
| S3 | I |
0.20 (0.16, 0.24) |
0.32 (0.28, 0.36) |
0.34 (0.31, 0.37) |
< 0.0001 |
0.32 (0.24, 0.36) |
0.32 (0.28, 0.36) |
0.32 (0.29, 0.35) |
0.62 | |
| I/IIa | N/A | N/A | N/A | - |
0.00 (0.00, 0.04) |
0.00 (0.00, 0.02) |
0.01 (0.00, 0.02) |
< 0.0001 | ||
| IIa |
0.32 (0.24, 0.40) |
0.26 (0.22, 0.30) |
0.30 (0.27, 0.33) |
< 0.0001 |
0.36 (0.32, 0.44) |
0.38 (0.32, 0.42) |
0.37 (0.34, 0.41) |
0.74 | ||
| IIa/IIx |
0.48 (0.40, 0.56) |
0.42 (0.38, 0.46) |
0.36 (0.33, 0.39) |
< 0.0001 |
0.28 (0.20, 0.32) |
0.26 (0.22, 0.32) |
0.27 (0.24, 0.30) |
0.89 | ||
| IIx | N/A | N/A | N/A | - |
0.00 (0.00, 0.04) |
0.02 (0.00, 0.02) |
0.02 (0.01, 0.03) |
< 0.0001 | ||
| S4 | I |
0.12 (0.08, 0.16) |
0.10 (0.08, 0.12) |
0.11 (0.09, 0.13) |
< 0.0001 |
0.12 (0.08, 0.16) |
0.08 (0.08, 0.14) |
0.12 (0.09, 0.14) |
0.87 | |
| I/IIa | N/A | N/A | N/A | - | N/A | N/A | N/A | - | ||
| IIa |
0.56 (0.48, 0.64) |
0.48 (0.44, 0.52) |
0.54 (0.50, 0.57) |
< 0.0001 |
0.48 (0.44, 0.56) |
0.50 (0.44, 0.56) |
0.50 (0.47, 0.53) |
0.54 | ||
| IIa/IIx |
0.32 (0.25, 0.40) |
0.40 (0.36, 0.44) |
0.31 (0.8, 0.34) |
< 0.0001 |
0.36 (0.28, 0.40) |
0.34 (0.30, 0.38) |
0.34 (0.31, 0.38) |
0.58 | ||
| IIx | N/A |
0.02 (0.00, 0.04) |
0.04 (0.03, 0.05) |
< 0.0001 |
0.04 (0.00, 0.04) |
0.04 (0.02, 0.06) |
0.03 (0.02, 0.05) |
0.16 | ||
| S5 | I |
0.24 (0.20, 0.28) |
0.18 (0.14, 0.22) |
0.24 (0.21, 0.27) |
< 0.0001 |
0.28 (0.24, 0.36) |
0.28 (0.24, 0.34) |
0.29 (0.26, 0.31) |
0.57 | |
| I/IIa | N/A |
0.02 (0.00, 0.04) |
0.03 (0.02, 0.04) |
< 0.0001 |
0.04 (0.00, 0.08) |
0.04 (0.02, 0.06) |
0.05 (0.03, 0.06) |
< 0.01 | ||
| IIa |
0.64 (0.60, 0.72) |
0.58 (0.54, 0.62) |
0.55 (0.52, 0.58) |
< 0.0001 |
0.48 (0.40, 0.56) |
0.48 (0.44, 0.54) |
0.48 (0.44, 0.51) |
0.26 | ||
| IIa/IIx |
0.04 (0.00, 0.08) |
0.18 (0.14, 0.22) |
0.16 (0.14, 0.18) |
< 0.0001 |
0.16 (0.12, 0.20) |
0.16 (0.14, 0.20) |
0.16 (0.14, 0,19) |
0.78 | ||
| IIx |
0.08 (0.04, 0.12) |
0.04 (0.02, 0.06) |
0.02 (0.10, 0.03) |
< 0.0001 |
0.00 (0.00, 0.04) |
0.02 (0.00, 0.04) |
0.02 (0.01, 0.03) |
< 0.001 | ||
| S6 | I |
0.60 (0.52, 0.68) |
0.68 (0.64, 0.72) |
0.61 (0.58, 0.64) |
< 0.0001 |
0.64 (0.56, 0.68) |
0.62 (0.58, 0.66) |
0.62 (0.59, 0.65) |
0.45 | |
| I/IIa |
0.04 (0.00, 0.08) |
0.04 (0.02, 0.06) |
0.07 (0.05, 0.08) |
< 0.0001 |
0.04 (0.04, 0.08) |
0.06 (0.04, 0.08) |
0.05 (0.04, 0.07) |
< 0.01 | ||
| IIa |
0.20 (0.12, 0.24) |
0.16 (0.12, 0.20) |
0.21 (0.18, 0.24) |
< 0.0001 |
0.24 (0.16, 0.28) |
0.22 (0.18, 0.26) |
0.22 (0.19, 0.25) |
0.48 | ||
| IIa/IIx |
0.12 (0.08, 0.16) |
0.10 (0.08, 0.12) |
0.10 (0.08, 0.12) |
< 0.0001 |
0.08 (0.04, 0.12) |
0.08 (0.06, 0.12) |
0.09 (0.07, 0.11) |
0.15 | ||
| IIx |
0.04 (0.00, 0.08) |
0.02 (0.00, 0.04) |
0.01 (0.00, 0.20) |
< 0.0001 | N/A |
0.00 (0.00, 0.02) |
0.00 (0.00, 0.01) |
< 0.0001 | ||
| S7 | I |
0.24 (0.20, 0.32) |
0.24 (0.20, 0.28) |
0.21 (0.18, 0.24) |
< 0.0001 |
0.21 (0.16, 0.28) |
0.22 (0.18, 0.26) |
0.22 (0.19, 0.24) |
0.20 | |
| I/IIa | N/A |
0.02 (0.00, 0.04) |
0.02 (0.01, 0.03) |
< 0.0001 |
0.00 (0.00, 0.04) |
0.00 (0.00, 0.02) |
0.01 (0.00, 0.02) |
< 0.0001 | ||
| IIa |
0.32 (0.24, 0.40) |
0.32 (0.28, 0.36) |
0.40 (0.37, 0.43) |
< 0.0001 |
0.42 (0.36, 0.48) |
0.42 (0.38, 0.47) |
0.42 (0.39, 0.46) |
0.88 | ||
| IIa/IIx |
0.20 (0.12, 0.24) |
0.24 (0.20, 0.28) |
0.22 (0.19, 0.25) |
< 0.0001 |
0.21 (0.16, 0.28) |
0.22 (0.18, 0.26) |
0.22 (0.20, 0.25) |
0.83 | ||
| IIx | N/A | N/A | N/A | - | N/A | N/A | N/A | - | ||
| S8 | I |
0.64 (0.57, 0.71) |
0.61 (0.56, 0.66) |
0.60 (0.56, 0.63) |
< 0.0001 |
0.64 (0.56,0.68) |
0.62 (0.58, 0.68) |
0.63 (0.60, 0.66) |
0.61 | |
| I/IIa |
0.04 (0.00, 0.08) |
0.04 (0.02, 0.06) |
0.02 (0.01, 0.03) |
< 0.0001 |
0.00 (0.00, 0.04) |
0.02 (0.00, 0.04) |
0.02 (0.01, 0.03) |
< 0.0001 | ||
| IIa |
0.16 (0.12, 0.21) |
0.16 (0.12, 0.20) |
0.25 (0.22, 0.28) |
< 0.0001 |
0.24 (0.20, 0.29) |
0.24 (0.20, 0.28) |
0.24 (0.21, 0.27) |
0.34 | ||
| IIa/IIx |
0.17 (0.12, 0.21) |
0.18 (0.14, 0.22) |
0.13 (0.11, 0.15) |
< 0.0001 |
0.12 (0.08, 0.16) |
0.10 (0.08, 0.14) |
0.10 (0.08, 0.13) |
0.48 | ||
| IIx | N/A | N/A | N/A | - | N/A | N/A | N/A | - | ||
Data are median (25th and 75th percentiles). S1 through S8 are subjects 1 through 8. P values are from Kurskal-Wallis tests across the number of fibers (i.e., 25, 50, 100) within the Ordered and Random selection of phenotyped muscle fibers. N/A, no fibers of this type were detected.