|Not full or partial, but full and partial squats will yield maximal performance increases in trained athletes.|
When it comes to strength gains on squats, incorporating partial lifts - something that is common practice among strength trainers, anyway (Harris. 2000; Stone. 2000; Clark. 2008 & 2011), is in fact an effective training method for improving maximal strength and early force-time curve characteristics in men with previous strength training experience.
Speaking of men with previous strength training experience, the subjects of the study that was conducted by Caleb Bazyler, Kimitake Sato, Craig Wassinger, Hugh Lamont, and Michael Stone, were 18 recreationally trained college aged males with at least 1 year of resistance training experience on the squat (>=1.3 body mass).
"Throughout the study, subjects were instructed to cease any supplementation use, refrain from lower-body resistance training outside of the study, and they were instructed not to participate in physical activity 24 hours before testing or training sessions. Subjects also completed a dietary log 24 hours before both preintervention testing sessions and were instructed to replicate the log for postintervention testing." (Bazyler. 2014)The subjects trained according to a classic block-periodized model to control for volume and intensity manipulation (28,33). In that, the scientists included heavy and light days with weights that differed by 10-15% "to manage fatigue and avoid training to failure" (Bazyler. 2014). The load for the squat and partial squat was calculated using percentage of preintervention 1RM.
- All training sessions were supervised to ensure correct technique and safety.
- Each training session began with a dynamic warm-up followed by warm-up sets on squat.
- The F group performed full squats only.
- The FP group performed full squats followed by partial squats (from 100° knee angle to lockout position).
|Figure 1: Changes in 1RM squat and 1RM partial squat (left) and changes in isometric squat peak force (IPFa) at 90 and 120° of knee flexion. 180° is full extension (Bazyler. 2014).|
- Tip: Partials work with back exercises, as well! Doing partials in the contracted position at the end of almost every back / pulling movement is going to increase the activation of the target muscle | learn more in the SuppVersityEMG Series.the full squat increasing the peak performance at a knee-angle of 90° (lower portion of the squat) to a significantly greater extend, and
- the full + partial squat increasing the peak performance at a knee-angle of 120° (upper portion of the squat) to a significantly greater extend,
|Figure 2: Changes in impulse scaled at 90° and 120° knee-angle (Bazyler. 2014).|
|"That's not 90°, yet. Go deeper, if you want to see results!"|
A very similar result that is even more closely relate to the study at hand was presented in another study I wrote about. A study by Blomquist et al. in their 2012 study which clearly proves that full squats are better strength builders than partial squats (only!).
|Figure 3: changes in force-time curve with training (Bazyler. 2014)|
As you can see the overall increase in force development over the 250s periods the researchers assessed increased to a slightly greater extent in the FP vs. F group.
An advantage that should pay off during any event in terms of increased maximal loads, at the latest, when it comes to doing squats for reps.
No changes in body comp - at least none that were different between groups. As Bazyler et al. point out, "[t]here was no statistical difference between groups during pre- and posttesting for any of the anthropometric variables. A time effect was found for body fat percentage (p <= 0.05). Body fat percentage decreased statistically by 10.3 ± 12.4%, d = 0.27 (p = 0.027) in the F group; however, the decrease did not reach statistical significance in the FP group, 5.3 ± 11.1%, d = 0.12 (p = 0.102)" (Bazyler. 2014)Whether or to which extend the previously discussed advantages of the full + partial squat regimen were related to the overall increase in intensity and volume (see Figure 4) is difficult to tell - the significant correlation Bazyler et al. found between the overall relative training intensity and the pre- to post 1RM squat change (r = 0.64, p = 0.003) would certainly suggest that there is a close relationship between training intensity and strength gains.
|Figure 4: Microcycle volume load (left) and relative training intensity (Bazyler. 2014)|
- Bazyler, Caleb D., et al. "The Efficacy of Incorporating Partial Squats in Maximal Strength Training." Journal of strength and conditioning research/National Strength & Conditioning Association (2014).
- Clark, Ross A., Adam L. Bryant, and Brendan Humphries. "An examination of strength and concentric work ratios during variable range of motion training." The Journal of Strength & Conditioning Research 22.5 (2008): 1716-1719.
- Clark, Ross A., et al. "The influence of variable range of motion training on neuromuscular performance and control of external loads." The Journal of Strength & Conditioning Research 25.3 (2011): 704-711.
- Harris, Glenn R., et al. "Short-term performance effects of high power, high force, or combined weight-training methods." The Journal of Strength & Conditioning Research 14.1 (2000): 14-20.
- Stone, Michael H., et al. "Comparison of the effects of three different weight-training programs on the one repetition maximum squat." The Journal of Strength & Conditioning Research 14.3 (2000): 332-337.