Table 3 Summary of the SM dose-physiological response relationship in animal studies
Studies | Dosage parameters | Sample size | Spine level | Muscle spindle activity - main results |
|---|---|---|---|---|
[30] Cao et al., 2013 | Thrust forces: 25, 55, 85% of BW | n = 112 cats | L6 | ● Consistent increase in MIF for 1 mm thrust amplitude. |
Thrust displacements: 1, 2 or 3 mm | ●No specific trend associated to modulation in forces and displacements | |||
Thrust durations: 0,25,50,75,100,150,200, 250 ms | ||||
[35] Pickar et al., 2006 | Thrust forces: 33, 66, 100% of BW | n = 46 cats | L6 | ●Data suggest that decreasing thrust duration increases ΔMIF |
Thrust duration: 25, 50, 100, 200, 400 or 800 ms | ● There is a threshold effect for duration for which the discharge greatly increases | |||
[36] Pickar et al., 2007 | Thrust displacement: 1 or 2 mm | n = 54 cats | L6 | ● Data suggest that decreasing thrust duration increases ΔMIF |
Thrust duration: 12.5, 25, 50, 100, 200, 400 ms | ||||
● Peak thrust amplitude (1 mm compared to 2 mm) influence ΔMIF | ||||
[37] Reed et al., 2013 | Thrust forces: 25, 55, 85% of BW | n = 112 cats | L6 | ● Data suggest that decreasing thrust duration increases mean spindle discharge through range of forces. |
Thrust displacement: 1, 2 or 3 mm | ● Through a range of force durations, increasing force seems to increase ΔMIF. | |||
Thrust durations: 25, 50, 75, 100, 200, 250 ms | ● For most thrust duration, peak thrust displacement did not influence ΔMIF. | |||
● Increasing force rates increased MIF | ||||
[38] Reed et al., 2015 | Thrust force: ranges from 68 N to 122 N | n = 1 cat | L7 | ● Data suggest that increasing force leads to increase ΔMIF. |
[39] Reed et al., 2014 | Preload variation: 18% or 43% of thrust force | n = 20 cats | L6 | ● Increasing longer preload duration (4 s compared to 1 s) increases ΔMIF. |
Thrust durations: 1 or 4 s (Thrust force: 55% of BW) | ||||
● A smaller magnitude of preload (18% compared to 43%) increases ΔMIF | ||||
● The highest preload magnitude and longest duration led to a significantly greater mean decrease in resting spindle discharge | ||||
[40] Reed et al., 2017 | Thrust force: 22 N, 44 N or 67 N | n = 6 cats | L6 | ● Data suggest that increase in force increased the time required until the first action potential. |