Finger blood flow measured in the unexposed (left) 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 | 23.2 (1.7) | 28.6 (2.0) | 27.4 (2.2) | 26.4 (2.3) | 24.4 (2.2) | 26.1 (2.8) |
| Exposure (min): | ||||||
| E 0.5 | 27.6 (2.8) | 27.0 (2.0) | 25.3 (2.1) | 23.8 (3.1) | 19.4 (2.0) | 22.4 (3.0) |
| +19.5% (−25.0% to 64.0%) | −3.0% (−33.4% to 27.4%) | −3.5% (−37.2% to 30.3%) | −12.1% (−37.8% to 13.7%) | −20.6% (−54.8% to 13.5%) | −10.9% (−51.6% to 29.7%) | |
| E 1.5 | 27.5 (3.5) | 27.2 (1.4) | 22.4 (1.5) | 24.8 (3.6) | 22.0 (2.6) | 23.1 (2.5) |
| +18.5% (−26.0% to 63.0%) | −2.9% (−33.3% to 27.5%) | −12.8% (−46.5% to 21.0%) | −8.0% (−33.8% to 17.8%) | −7.8% (−41.9% to 26.4%) | −7.4% (−48.1% to 33.2%) | |
| E 3.5 | 25.9 (3.0) | 26.1 (1.5) | 25.9 (2.0) | 24.5 (2.8) | 20.5 (2.0) | 19.8 (2.3) |
| +13.3% (−31.2% to 57.8%) | −6.3% (−36.7% to 24.1%) | −2.1% (−35.8% to 31.7%) | −6.7% (−32.5% to 19.0%) | −12.1% (−46.2% to 22.0%) | −23.4% (−64.0% to 17.3%) | |
| E 5.5 | 30.4 (2.9) | 30.8 (2.6) | 30.2 (2.8) | 23.9 (2.8) | 21.0 (2.7) | 17.9 (2.3) |
| +32.5% (−12.0% to 77.0%) | +11.9% (−18.5% to 42.3%) | +12.7% (−21.1% to 46.4%) | −10.1% (−35.8% to 15.7%) | −14.7% (−48.8% to 19.4%) | −29.4% (−70.1% to 11.2%) | |
| E 7.5 | 29.8 (3.1) | 25.7 (1.5) | 25.9 (2.9) | 23.0 (2.8) | 24.4 (2.9) | 19.5 (3.1) |
| +27.4% (−17.0% to 71.9%) | −5.0% (−35.4% to 25.4%) | −3.9% (−37.7% to 29.8%) | −13.8% (−39.5% to 12.0%) | 0% (−34.1% to 34.1%) | −23.0% (−63.7% to 17.6%) | |
| E 15 | 32.5 (2.7) | 25.8 (1.3) | 27.3 (3.1) | 21.5 (3.0) | 18.9 (2.8) | 19.3 (2.2) |
| +43.7% (−0.7% to 88.2%) | −3.9% (−34.4% to 26.4%) | +0.5% (−33.3% to 34.2%) | −17.8% (−43.6% to 8.0%) | −19.9% (−54.1% to 14.2%) | −17.7% (−58.4% to 22.9%) | |
| Recovery (min): | ||||||
| R 0.5 | 28.3 (2.4) | 29.8 (2.8) | 29.9 (1.9) | 27.1 (2.8) | 24.2 (2.0) | 29.0 (3.7) |
| +26.0% (−18.5% to 70.5%) | +6.9% (−23.5% to 37.2%) | +12.6% (−21.2% to 46.3%) | +1.6% (−24.2% to 27.3%) | +8.5% (−25.6% to 42.6%) | +18.6% (−22.0% to 59.3%) | |
| R 1.5 | 26.7 (2.3) | 27.5 (1.7) | 26.8 (2.6) | 23.9 (2.3) | 26.4 (2.2) | 24.0 (2.1) |
| +15.2% (−29.3% to 59.7%) | +1.6% (−28.8% to 32.0) | +1.4% (−32.3% to 35.2%) | −9.6% (−35.3% to 16.2%) | +16.0% (−18.1% to 50.2%) | −3.1% (−43.7% to 37.6%) | |
| R 3.5 | 26.6 (2.3) | 26.3 (1.5) | 26.9 (2.6) | 24.8 (2.7) | 24.3 (2.2) | 26.2 (1.8) |
| +18.3% (−26.2% to 62.8%) | −3.2% (−33.6% to 27.2%) | +1.8% (−31.9% to 35.6%) | −5.5% (−31.3% to 20.3%) | +3.1% (−31.1% to 37.2%) | +10.3% (−30.3% to 51.0%) | |
| R 5.5 | 27.8 (2.6) | 25.2 (1.3) | 27.0 (2.2) | 26.7 (3.2) | 28.4 (2.4) | 24.8 (2.7) |
| +21.4% (−23.1% to 65.9%) | −8.4% (−38.8% to 22.0%) | +2.1% (−31.7% to 35.8%) | −1.0% (−26.7% to 24.7%) | +25.5% (−8.6% to 59.7%) | +8.8% (−31.9% to 49.5%) | |
| R 7.5 | 26.3 (2.0) | 26.2 (1.6) | 25.8 (1.6) | 27.2 (3.6) | 23.2 (2.2) | 23.6 (1.8) |
| +16.7% (−27.8% to 61.2%) | −1.8% (−32.2% to 28.6%) | −1.4% (−35.2% to 32.3%) | +0.4% (−25.3% to 26.2%) | −2.3% (−36.5% to 31.8%) | +2.9% (−37.8% to 43.5%) | |
| R 15 | 27.9 (2.5) | 24.5 (1.1) | 25.5 (2.9) | 27.5 (3.1) | 21.7 (2.4) | 23.5 (1.7) |
| +21.3% (−23.2% to 65.8%) | −9.7% (−40.1% to 20.8%) | −1.3% (−35.0% to 32.5%) | +3.1% (−22.6% to 28.9%) | −7.5% (−41.6% to 26.7%) | +0.7% (−40.0% to 41.3%) | |
| R 22.5 | 26.8 (2.6) | 25.3 (0.9) | 24.7 (1.8) | 22.2 (2.5) | 23.0 (2.8) | 20.1 (1.6) |
| +18.2% (−26.2% to 62.7%) | −6.9% (−37.3% to 23.5%) | −3.9% (−37.7% to 29.8%) | −15.2% (−40.9% to 10.6%) | −1.6% (−35.7% to 32.5%) | −15.2% (−55.8% to 25.5%) | |
| R 30 | 25.6 (2.4) | 27.0 (1.5) | 23.3 (2.5) | 20.7 (2.2) | 17.0 (1.7) | 14.7 (1.7) |
| +12.2% (−32.3% to 56.7%) | −1.7% (−32.1% to 28.7%) | −9.9% (−43.7% to 23.8%) | −20.7% (−46.5% to 5.1%) | −24.8% (−58.9% to 9.3%) | −41.4% (−0.8% to −82.1%) | |
| R 37.5 | 25.3 (1.9) | 26.7 (2.0) | 18.4 (2.8) | 20.9 (1.6) | 13.0 (1.3) | 13.6 (1.2) |
| +14.5% (−30.0% to 58.9%) | −2.5% (−32.9% to 27.9%) | −28.7% (−62.5% to 5.0%) | −19.1% (−44.9% to 6.7%) | −42.3% (−8.2% to −76.5%) | −43.7% (−3.0% to −84.3%) | |
| R 45 | 29.0 (2.9) | 24.9 (2.1) | 18.3 (3.1) | 18.1 (2.0) | 11.4 (1.2) | 15.2 (1.8) |
| +30.7% (−13.7% to 75.2%) | −9.3% (−39.7% to 21.1%) | −29.9% (−63.6% to 3.9%) | −30.5% (−4.7% to −56.3%) | −49.7% (−15.6% to −83.9%) | −39.1% (−2.5% to −75.7%) | |
| ANCOVA (p value) | 0.28 | 0.33 | 0.014 | 0.007 | <0.0001 | 0.0003 |
Mean (SEM) values (ml/100 ml/min) and mean (95% CI) values 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.