|"That's not 90°, yet. Do deeper!"|
The good news is that it appears as someone has heard my lamentations about the scarcity of respective research, or - what's in this case more probably - feel the same about the necessity to generate data that would be necessary to base our workout protocols on more than just "hearsay", hypothesis and "N=1 experiences" and a single study.
Ok, enough kiddin' around let's get to the facts
|Table 1: McMahon's interpretation of an "ecologically valid resistance training program"; * denotes static holds for time in s, DL = double, SL = single legged (McMahon. 2013)|
With the the specified angle being defined as the "position at which the training load is held isometrically for two seconds",
- the 50° regimen involved a shorter ROM (SR) in the dynamic phase of the exercise and thus a shorter ‘average muscle length’, whereas
- the 90° regimen involved a longer ROM (LR) in the dynamic phase of the exercise and thus a longer ‘average muscle length’ *you will learn more about the importance of muscle lengthening later this week, so stay tuned!
|Figure 1: Cross sectional area (CSA) of the vastus lateralis measured at 25, 50 and 75% of the femur length for the full range (LR), partial range (SR) and a non-exercised control group (McMahon. 2013)|
"CSA increased significantly (p<0.05) relative to baseline following training at all sites in both training groups. The significant training effect remained during the whole detraining period in both training groups at both 50% and 75%, but was not evident at 25% of femur length after week 10. There was a trend for LR to exhibit greater relative gains in a CSA compared to SR at all sites, which was significant at week 8 at 75% of femur length. It was found that there was not only a main training effect (p<0.05) but a main group effect after week 8 (p<0.05) with LR exhibiting a 59±15% compared to SR showing 16±10% increment in VL CSA." (McMohan. 2013)To the surprise of the researchers, the "following the first two weeks of detraining the group effect was no longer evident (p=0.07)" (McMohan. 2012). In the end, the existing advantage of training over the full-ROM, as pronounced as it may be at the CSA75 site, is thus short lived in this group of previously non-resistance-traind 26 volunteers (14 males and 12 females). The fasicle length, which increased by
23±5%, 19±4%, 16±4% at weeks 8, 10 and 12 in the LR and by only 10±2%, 6±2% and 2±2% in the SR group (data not shown), on the other hand, were persistent - yet only in the full range (LR) group.
"And body fat? What about the body fat"
|Crossfit doesn't fit well with everyone. In fact, you have to be pretty fit already if you intend to benefit - specifically if you don't have someone who tailors the workouts to your specific needs. If you the shed 8% of your already low 16% body fat in 10 weeks workout routine I wrote about in February, chance is you'll just get injured or burned out (learn more)|
"[...] main effect of group remained during weeks 10 and 12, as SR regressed toward baseline by week 12, whereas LR still possessed significant losses at this phase (-10±6%)" (McMahon. 2013)and that there was a similar trend seen at 75% where a main effect of both group and training existed at week 8 (p<0.05) - even if the latter vanished in the course of the 4-week detraining period 7±3% SL and 9±1% LR).
Regional growth and angle-specific strength gains
Contrary to all previously reported values, which were - if they were group specific at all - regionally different, the changes in strength showed - as you would expect it - an angular specificity. While both groups did increase their strength, there were more than just minute differences between the partial (SR) an the full ROM (LR) groups:
- at the end-ranges, the maximal volunary contractive force increased 5±10 for SR at 50° and 30±5% for LR at 90°, respectively
- there was evidence of angular specificity of training in both groups with SR significantly (p>0.05) increasing MVCs at 50, 60, 65, and 70° , only, wheres the participants in the LR increased their MVCs values over the entire angular range.
"By week 10, both groups displayed an average 6±2% strength reduction (relative to the post-training strength values), with SR not significantly above baseline (0±2%) in contrast to LR remaining significantly above both baseline (p<0.05) and SR (p=0.027) at weeks 10 and 12."Overall, the changes in contractile force and the angle at which they were elicited reflect the structural changes that were brought about by the more pronounced muscle lengthening that's a prerogative of training over the full range of motion (ROM).
Handpicked suggested reads:
The Jack-of-All-Traits Leg Workout from the Sáez de Villarreal study I discussed on July 15, 2012, would also be something you may want to look into if you need some inspiration for your own routine.
- SuppVersity EMG Series - Gluteus maximus, Quadriceps femoris, Gastrocnemius, Soleus & More: The Very Best Exercises for Tree-Trunk Legs and Herculean Calves (read more)
- The Step-By-Step to Your Own Workout Routine Guide (read it)
- All posts leg training at the SuppVersity (read them)
- "hypothesis, n.". OED Online. March 2013. Oxford University Press. 6 May 2013 <http://www.oed.com/view/Entry/90588?redirectedFrom=hypothesis>.
- Eugene McMahon G, Onambélé-Pearson G. Impact of range-of-motion during
ecologically valid resistance training protocols, on muscle size, subcutaneous fat
and strength. J Strength Cond Res. 2013 Apr 26.[Epub ahead of print]