All NJM results are presented in APPENDIX D table 3 and 7. NJM are present in form of bar charts in tables 13-17 and time interaction in figure 19 and 20. Out of the 12 peak NJM variables (not including the hip-to-knee ratios) 7 reached a moderate to large ES in statistically significant differences between NBBS and WBBS (p<0.05). 5 of these variables were higher in both loading conditions for NBBS and WBBS, strengthening the result. These 5 variables included 4 variables that were higher in the WBBS: 3-D hip NJM, hip sagittal NJM, Hip transverse NJM, knee sagittal NJM, and knee frontal NJM (p<0.05) and one variable that was higher in the NBBS: knee sagittal NJM (p<0.05). At 70% of 1 RM, hip frontal plane NJM was significantly higher in the WBBS (p<0.05). At 85% of 1 RM, L5/SI NJM and 3-D knee NJM were significantly higher in NBBS (p<0.05).
In terms of effects of load within the same squat width, 8 out of 12 variables reached a moderate to large ES (p<0.05). Of these 8 variables, 4 were higher in both WBBS and NBBS load comparisons, further strengthening the result. These 4 variables that were higher in both WBBS and NBBS
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comparisons included higher 3D L5/SI NJM (p<0.05), 3D hip NJM (p<0.01), hip sagittal NJM (p<0.01), and 3-D knee NJM (p<0.01), all reaching large ES. The other 4 variables that were higher were L5/SI sagittal NJM, hip frontal NJM, knee frontal NJM, and knee transverse NJM in the NBBS load comparison (p<0.01) and higher knee sagittal NJM in the WBBS load comparison (p<0.05), all reaching moderate to large ES.
FIGURE 13. 3-D NJM for L5/SI, Hip, and knee. Both width and load interactions included. * = indicates statistically significant p<0.05, ** = indicates very statistically significant p<0.01, *** = indicates highly statistically significant p<0.001. A substantial amount of interactions can be found for both squat width and load. The 3-D hip NJM had the most interactions and was the only 3-D NJM that showed significance within widths at both 70 and 85% of 1-RM loads, in this case in favor for the WBBS. The effect of width on 3-D lower lumbar and knee NJM were less clear.
Except for the lower lumbar, load interactions ranged from very- to highly significant between both the WBBS and NBBS loads.
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FIGURE 14. L5/SI NJM in all 3 planes. Both width and load interactions included. * = indicates statistically significant p<0.05, ** = indicates very statistically significant p<0.01, *** = indicates highly statistically significant p<0.001. Due to the spine moving mostly in the sagittal in the only interaction found was between loads, in this case the NBBS.
FIGURE 15. Hip NJM in all 3 planes. Both width and load interactions included. * = indicates statistically significant p<0.05, ** = indicates very statistically significant p<0.01, *** = indicates
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highly statistically significant p<0.001. Most movement in the BBS is found in the sagittal plane, but significant contributions to total hip torque are also produced from the frontal plane and even to some extent from the transverse plane. These contributions become further evident in the WBBS.
FIGURE 16. Knee NJM in all 3 planes. Both width and load interactions included. * = indicates statistically significant p<0.05, ** = indicates very statistically significant p<0.01, *** = indicates highly statistically significant p<0.001. At the knee, sagittal plane NJM are also logically the largest contributor, in this case in favor of the NBBS. Interestingly, frontal plane knee NJM were not far behind and were significantly higher in the WBBS. Load interactions were found in all planes, but more so in the NBBS.
Out of the 2 hip-to-knee NJM ratios measured both reached large ES for higher hip-to-knee ratios in WBBS (p<0.01). Large ES was present in both loading conditions, further strengthening the result.
No statistical significance was found for the load condition (p>0.05).
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FIGURE 17. Hip-to-knee NJM ratios. Both width and load interactions included. * = indicates statistically significant p<0.05, ** = indicates very statistically significant p<0.01, *** = indicates highly statistically significant p<0.001. Although both extensor and 3-D NJM ratios reached very statistically significant levels in favor the WBBS, the ratio was clearly lowered in the 3-D divide, especially in the WBBS. This was mostly due to that frontal plane knee NJM were higher in the WBBS, leading to a reduction in hip dominance.
FIGURE 18: Resultant force vector behavior seen from the front in the NBBS (A) and WBBS (B) at 70% of 1 RM. Screenshot taken from the NEXUS program at approximately 70% of the ascent phase. The significant frontal plane knee NJM was found due that the resultant force vector leans medially creating a significant knee adduction demand, further increasing when width was increased.
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FIGURE 19. Group average of moment-time curves for the hip (sagittal, frontal, transverse) and force-time curves for vertical and lateral (medially directed) directions in the NBBS (A) and WBBS (B). Data taken as an average from the 70% and 85% loads from the first repetition. Here we can see how the external forces interact with the NJM. The medial-lateral force curve is quite clearly coordinated with the frontal and transverse plane NJM (hip abduction & internal rotation) but not the sagittal plane NJM, mostly evident in the ascent phase (around 75% of the total repetition time)
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FIGURE 20. Group average of moment-time curves for the knee (sagittal, frontal) and force-time curves for vertical and lateral (medially directed) directions in the NBBS (A) and WBBS (B). Data taken as an average from the 70% and 85% loads from the first repetition. Transverse plane
disclosed due to no significant interactions. Here we can also see how the external forces interact with the NJM. Again, a connection between the medial-lateral force and the frontal plane NJM can be observed mostly in the ascent phase, but not the vertical force.