Finger blood flow measured in the exposed (right) middle finger of 10 healthy subjects before, during and after a 15 minute exposure to static load (contact force 10 N) and vibration with different combinations of frequencies (Hz) and unweighted acceleration magnitudes (m/s2 rms) but with the same frequency weighted acceleration (5.5 m/s2 rms) according to the frequency weighting of ISO 5349
| Static load | Vibration 16 Hz, 5.5 m/s2 | Vibration 31.5 Hz, 11 m/s2 | Vibration 63 Hz, 22 m/s2 | Vibration 125 Hz, 44 m/s2 | Vibration 250 Hz, 88 m/s2 | |
| Before exposure | 24.3 (2.1) | 25.5 (1.9) | 23.4 (2.6) | 25.1 (2.5) | 24.1 (2.0) | 26.7 (2.3) |
| Exposure (min): | ||||||
| E 0.5 | 18.5 (2.4) | 17.9 (2.9) | 9.7 (1.6) | 11.0 (1.4) | 11.0 (1.9) | 12.6 (1.8) |
| −23.9% (−65.3% to 17.6%) | −30.2% (−63.9% to 3.5%) | −52.8% (−7.1% to −98.6%) | −54.9% (−21.1% to −88.8%) | −52.1% (−13.4% to −90.8%) | −50.2% (−17.3% to −83.2%) | |
| E 1.5 | 22.5 (2.7) | 18.9 (2.7) | 8.9 (1.3) | 11.5 (1.5) | 11.3 (2.1) | 13.3 (2.1) |
| −6.7% (−48.2% to 34.7%) | −24.4% (−58.1% to 9.3%) | −54.1% (−8.4% to −99.9%) | −51.4% (−17.6% to −85.7%) | −49.0% (−10.3% to −87.7%) | −48.4% (−15.4% to −81.4%) | |
| E 3.5 | 23.2 (2.7) | 17.3 (3.3) | 9.6 (1.2) | 9.8 (1.0) | 9.2 (1.3) | 11.6 (1.7) |
| −4.3% (−45.8% to 37.1%) | −33.0% (−66.7% to 0.7%) | −53.6% (−7.8% to −99.3%) | −56.4% (−22.6% to −90.2%) | −57.2% (−18.6% to −95.9%) | −54.7% (−21.7% to −87.7%) | |
| E 5.5 | 23.4 (3.0) | 19.6 (3.4) | 9.3 (1.5) | 10.7 (1.3) | 11.0 (2.0) | 10.8 (1.5) |
| −0.1% (−41.6% to 41.3%) | −22.4% (−56.1% to 11.3%) | −55.3% (−11.0% to −99.6%) | −52.6% (−18.7% to −86.4%) | −53.3% (−14.6% to −91.9%) | −57.4% (−24.4% to −90.4%) | |
| E 7.5 | 25.6 (3.2) | 17.4 (2.5) | 8.8 (1.2) | 11.2 (1.8) | 11.0 (1.9) | 12.8 (1.3) |
| +6.0% (−35.4% to 47.5%) | −30.5% (−64.2% to 3.2%) | −56.4% (−13.0% to −97.8%) | −52.3% (−18.5% to −86.1%) | −51.8% (−13.1% to −90.5%) | −49.8% (−16.8% to −82.8%) | |
| E 15 | 27.0 (3.9) | 15.2 (2.8) | 10.5 (2.0) | 11.5 (1.6) | 8.6 (1.2) | 11.5 (2.3) |
| +11.4% (−30.1% to 52.8%) | −39.5% (−5.8% to −73.3%) | −55.2% (−11.0% to −99.4%) | −50.7% (−16.8% to −84.5%) | −62.1% (−25.0% to −99.2%) | −58.5% (−25.5% to −91.5%) | |
| Recovery (min): | ||||||
| R 0.5 | 25.6 (3.0) | 27.7 (3.9) | 25.2 (2.8) | 24.7 (2.3) | 24.5 (2.6) | 24.4 (2.1) |
| +7.8% (−33.6% to 49.3%) | +7.8% (−25.9% to 41.5%) | +17.3% (−28.5% to 63.0%) | −0.1% (−34.0% to 33.8%) | +3.5% (−35.2% to 42.1%) | −7.3% (−40.3% to 25.7%) | |
| R 1.5 | 25.8 (2.9) | 26.8 (2.3) | 25.1 (2.3) | 24.1 (2.9) | 27.5 (3.5) | 23.9 (2.3) |
| +7.8% (−33.7% to 49.2%) | +6.4% (−27.3% to 40.1) | +21.9% (−23.9% to 67.6%) | −2.7% (−36.6% to 31.1%) | +17.2% (−21.5% to 55.9%) | −8.3% (−41.3% to 24.7%) | |
| R 3.5 | 26.1 (1.5) | 25.3 (3.0) | 24.6 (2.5) | 23.2 (1.7) | 25.5 (2.1) | 25.4 (3.1) |
| +15.0% (−26.4% to 56.5%) | −2.2% (−35.9% to 31.6%) | +18.3% (−27.5% to 64.0%) | −1.9% (−35.7% to 32.0%) | +7.2% (−31.4% to 45.9%) | −3.1% (−36.0% to 29.9%) | |
| R 5.5 | 27.5 (2.6) | 25.6 (2.9) | 23.9 (2.1) | 22.9 (1.9) | 27.2 (1.9) | 24.8 (2.4) |
| +19.2% (−22.3% to 60.6%) | −0.3% (−33.9% to 33.4%) | +16.1% (−29.7% to 61.8%) | −6.8% (−40.6% to 27.0%) | +18.3% (−20.3% to 57.0%) | −4.6% (−37.6% to 28.4%) | |
| R 7.5 | 27.4 (1.9) | 23.2 (2.1) | 22.1 (1.5) | 26.0 (3.3) | 23.4 (2.1) | 23.4 (2.0) |
| +20.8% (−20.6% to 62.3%) | −6.3% (−40.0% to 27.4%) | +12.1% (−33.6% to 57.9%) | +5.9% (−27.9% to 39.7%) | −2.2% (−40.8% to 36.5%) | −8.4% (−41.3% to 24.6%) | |
| R 15 | 27.1 (2.6) | 25.8 (2.4) | 23.0 (2.0) | 26.5 (2.5) | 23.4 (1.8) | 23.9 (1.9) |
| +13.3% (−28.1% to 54.8%) | +1.6% (−32.1% to 35.4%) | +14.4% (−31.3% to 60.1%) | +12.6% (−21.3% to 46.4%) | +3.4% (−35.2% to 42.1%) | −5.8% (−38.8% to 27.2%) | |
| R 22.5 | 22.9 (1.8) | 25.4 (2.4) | 21.4 (1.9) | 21.0 (1.9) | 20.1 (1.9) | 19.3 (2.1) |
| −1.4% (−42.9% to 40.0%) | −0.5% (−34.2% to 33.2%) | +7.5% (−38.3% to 53.2%) | −6.4% (−40.2% to 27.4%) | −12.9% (−51.5% to 25.8%) | −26.5% (−59.5% to 6.5%) | |
| R 30 | 22.0 (2.4) | 27.7 (3.2) | 20.5 (2.2) | 18.8 (1.9) | 15.1 (1.7) | 14.3 (1.0) |
| −6.4% (−47.9% to 35.0%) | +9.2% (−24.5% to 42.9%) | +2.3% (−43.5% to 48.0%) | −19.7% (−53.5% to 14.1%) | −35.1% (−73.8% to 3.6%) | −44.9% (−77.9% to 11.9%) | |
| R 37.5 | 22.8 (2.3) | 27.2 (2.5) | 15.1 (1.8) | 17.3 (1.3) | 12.4 (1.2) | 15.3 (1.7) |
| +0.2% (−41.2% to 41.7%) | +9.0% (−24.7% to 42.7%) | −23.6% (−69.4% to 22.1%) | −26.1% (−59.9% to 7.7%) | −45.9% (−7.3% to −84.6%) | −42.4% (−9.4% to −75.4%) | |
| R 45 | 26.9 (3.3) | 24.2 (2.7) | 15.8 (2.6) | 17.8 (2.2) | 13.2 (1.5) | 14.2 (2.0) |
| +15.3% (−26.2% to 56.7%) | −4.8% (−38.5% to 28.9%) | −20.9% (−66.6% to 24.9%) | −24.7% (−58.6% to 9.1%) | −44.4% (−5.7% to −83.0%) | −47.0% (−14.0% to −80.0%) | |
| ANCOVA (p value) | 0.12 | 0.0005 | <0.0001 | <0.0001 | <0.0001 | <0.0001 |
Mean (SEM) values (ml/100 ml/min) and mean (95% CI) for the percentage changes in finger blood flow compared with the measures before exposure are also given.
p Values of repeated measures analysis of covariance (ANCOVA) are adjusted by age, finger volume, and room temperature.