Squat or Sled? Study Compares Muscle Activation During Squatting & Sled Pushing - One For Quads, One For Hams!

Original image from the publication.

As Meaghan E. Maddigan, Duane C. Button and David G. Behm from the Memorial University of Newfoundland rightly point out, "the back squat is a traditional resistance training exercise." (Maddigan. 2014).

The use of resisted sled exercises, on the other hand, is a relatively new phenomenon of which we don't even know yet how it compares to the classics.

Accordingly, Maddigan et al. set out to compare the muscle activation between squatting and sled pushing on the activity of leg and trunk muscles in ten healthy resistance-trained men in the context of a randomized crossover design study.

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The study consisted of 2 preparation sessions and 2 testing sessions. Electromyographic (EMG) activity of the rectus femoris, biceps femoris, gastrocnemius, lower erector spinae, and the transversus abdominis/ internal obliques (TrA/IO) were monitored during a 20-step maximum push with the weighted sled apparatus and a 10 repetition maximum with a bilateral back squat.

All ten subjects were healthy resistance-trained men (age 24.6 years, mass 84.5 kg, height 178.3cm) who had at least 2 years of resistance training and squat experience and were also familiar with performing the sled exercises (however, the volume of squat experiences exceeded sled training volumes or training durations).

Figure 1: Average root mean square (RMS) EMG recorded in exercise phase 1, 2, and 3 (EMG signal was calculated over a 1-second segment of the concentric contraction phase of each step or repetition) from (A) rectus femoris, (B) biceps Femoris, (C) gastrocnemius, and (D) erector spinae during the concentric portion of the sled and squat exercises. Open circles represent the sled condition, whereas the filled squares represent the squat condition (Maddigan. 2014).

As you can see in Figure 1 there were nonsignificant trends for the rectus femoris ( p = 0.092: 8.6– 16.7%) and biceps femoris ( p = 0.09: 10.5–32.8%) to demonstrate higher activity with the sled and squat exercises, respectively. A result based on which you could conclude that

• squatting is better for the quads, while
• sled pushing is th better hamstring exercise

Maddigan et al. also observed main effects for condition with 61.2% greater gastrocnemius EMG with the sled exercise ( p = 0.01) and 74.5% greater erector spinae EMG activity with the squat (p = 0.002). For the transversus abdominis/ internal obliques, however, there were no significant differences between the exercises for the.

Building the Jack-of-All-Traits Legs Workout With Squats, Jump Squats and Body Weight Plyometrics? At Least for Physical Education Students that Seems to Work | more

Bottom line: As the authors write in their conclusion, "the sled and squat exercises provided similar EMG activity for the quadriceps, hamstrings, and ransversus abdominis/ internal obliques." In that the squat may be more favorable for developing the quads, while the sled is the better hamstring activator and calf (gastrocnemius) builder.

As Maddigan et al. say, the decision which of the exercises is "best" for you will depend "on the movement-training specificity of the sport" you compete in. "[E]ither exercise may be used in a training program while acknowledging the differences in gastrocnemius and erector spinae activity." (Maddigan. 2014)

One question remains, though. Will the long-term adaptations reflect the different EMG-activation in the study at hand? To a certain extend this will probably be the case, whether and to which extent you would make better progress with one over the other exercise and if it makes sense to do both (maybe in an A-B workout style) will still have to be elucidated | Comment on Facebook!

References:

• Maddigan, Meaghan E., Duane C. Button, and David G. Behm. "Lower-Limb and Trunk Muscle Activation With Back Squats and Weighted Sled Apparatus." Journal of strength and conditioning research/National Strength & Conditioning Association 28.12 (2014): 3346-3353.

VPX Pre- & Post-Workout Nutrition Gets "Sponsored" Scientific Approval: +4% Lean Mass, -6% Body Fat, +13% Upper and +21% Lower Body Strength in 29 Days

Image 1: Supplemental double-whammy. VPX' now
"scientifically proven" pre- & postworkout products

This is one of those cases, where I cannot decide whether I should applaud VPX or just shake my head... the scientist in me says: "Hey, you know how that is - with a research grant from the government cutting edge science is impossible, especially if you want to investigate something as 'profane' as building muscle". The cynic skeptic, on the other hand, whispers: "Come on, what results would you expect, if the study was financed by the producer of the supplement under scrutiny?" I guess I will applaud skeptically and exercise special caution in my analysis of the latest study from the Department of Health and Performance at Baylor University (Willoughby. 2011).

As in previous studies (Willoughby. 2007; Willoughby. 2009), Darryn S. Willoughby and his colleagues availed themselves of a buckload of VPX supplements and recruited 19 previously recreationally active, yet untrained (*) men with an average age of 22.8 +/-4.67 years, a height of 179.5 +/-6.38 cm and a total body mass of 79.1 +/-16.13 kg for another study into the effects of two supplements, which are supposed to "advance you to the next level of fitness" (VPX. 2011). Strength and body composition (body fat measured reliably by DEXA, not body-impedance), venous blood sampling and muscle biopsies were performed on day 0 and day 29 of the 4-week study period, in the course of which the participants underwent a standardized resistance training protocol (upper-/lower-body split, 4x à week), which mirrored the one that had been used in Willoughby. 2009 already (*).

Figure 1: Illustration of the training regimen (based on Willoughby. 2011)

The bodybuilding-type beginner 2x split training regimen is unquestionably a huge plus of the study (cf. figure 1). Performed twice a weak, this is what real world training would look like and so that it stands out of question that the results of the study will translate into practice - at least for everyone who has not touched a dumbbell more than thrice a week within the last 12 and abstained from all sorts of performance enhancing supplements and drugs within the last 3 months (*).

The NO Shotgun approach to protein NO SyntheSize??? 

Figure 2: Ingredient profiles of
No Shotgun and No SyntheSize

More important than the identical training regimen was yet obviously the supplementation protocol, to which the participants were assigned in a double-blind randomization process (on a side note: "double-blind" means that not only the subjects, but the scientists, as well, did not know which participants received the placebo and which ones the VPX products). While half of the subjects consumed a maltodextrose placebo (27g pre, 27g post workout), the subjects in the "NOSS" group consumed the same amount of NO Shotgun and NO SyntheSize as their pre- and posworkout supplement, respectively. Now, as the names imply, both supplements are intended to increase nitric oxide production and protein synthesis, yet with a focus on the former in NO Shotgun that is loaden with arginine and a heap of stimulants and a focus on the latter in NO SyntheSize, the composition of which is pretty similar (cf. figure 2), yet without the "Redline Energy & Meltdown Fat Burning Technology" ;-)

Although there were no specifically dietary guidelines, the research did at least collect some nutritional data based on a 4-day questionnaire all participants had to answer at the beginning and end of the study. While there was a slight reduction in the total caloric intake in the carb group (interestingly mainly from carbohydates), neither the intra-group changes, nor the inter-group differences reached statistical significance.

More muscle, less fat! Trainee, what more can you ask for?

That there were no differences is yet something you cannot say of the changes in body composition the study participants underwent in the course of this 28-day intervention.

Figure 3: Relative changes (compared to baseline) in body composition after 16 strength training sessions in 28 days with either 54g of maltodextrin or 27g of NO Shotgun and 27g NO Synthesize pre- and postworkout (Willoughby. 2011)

As a passing view of the relative changes (compared to baseline) in figure 3 show, the NOSS group (receiving NO Shotgun prior and NO SyntheSize post workout) registered significantly more pronounced elevations in fat free mass (p<.023 indicates that the chances that this was sheer coincidence are 23%) and - contrary to the carbohydrate group - lost -6% of their body fat, while the carb eaters added another 2% of adipose tissue to their love-handles.

Figure 4: Changes in upper and lower body strength (in kg/kg body weight during bench press and leg press at 1RM) after 16 strength training sessions in 28 days with either 54g of maltodextrin or 27g of NO Shotgun and 27g of NO Synthesize pre- and postworkout (Willoughby. 2011)

Interestingly, the lean mass increase went hand in hand with likewise (statistically) significantly greater (p-values see figure 4) increases in both upper (+13% vs. +1%) and lower (+21% vs. +11%) strength in the subjects in the NO Shotgun + NO SyntheSize groups.

* you may have wondered what all the asterisks in the previous paragraphs meant... well, they indicate specificities in the study design detractors may call "precautions that ensure that the VPX supplements are sitting pretty" ... I mean the exact same supplementation protocol performed on a bunch of veteran bodybuilders would probably not have elicited any measurable effects on body composition - keep that in mind when you interpret the results.

Now, it obviously should not surprise you that the protein (and leucine) loaden and creatine, beta-alanine spiked workout supplements outperform simple sugar water. It is thus more interesting to take another look at the data from the 2009 "NO Shotgun only"-study, Willoughby et al. have done (Willoughby. 2009). On the exact same training protocol, yet with only 27g of NO Shotgun or placebo 30min preworkout, the participants lost less body fat (-1.21%), but gained the exact same ~4% of lean mass and comparable increases in bench press and leg press 1RM (+8.82% and +18.4%, respectively).

Scientifically proven ingredients make scientifically proven products

I leave it up to you whether or not the results of this study will influence your next supplement purchase - after all, even the VPX guys will be aware that their supplements are not so unique that intelligent people like you would not be able to identify the key ingredients in their products (EAAs, hydrolized protein, creatine, beta alanine, some workout-boosting stimulants, etc.) and realize that there are way more than those two products which would probably have produced identically (within statistical margins) results, if, and here we've come full circle, if their respective manufacturers had the money and the balls to do scientific studies on their products.

Partial Reps, Full Strength? For Squats, Combining Both via Block Periodization Yields Greater Strength Gains During the Early Phase of the Movement in Trained Gymrats

Not full or partial, but full and partial squats will yield maximal performance increases in trained athletes.

In a recent study from the East Tennessee State and the California Lutheran University researchers were able to show the common wisdom that only full reps would guarantee full development is true, but not the be-all and end-all of strength training wisdom.

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.

Learn more about building muscle and strength at www.suppversity.com

Tri- or Multi-Set Training for Body Recomp.?

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Study Indicates Cut the Volume Make the Gains!

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.

Table 1: Overview of the strength training program. *RM = repetition maximum. †F (full ROM) performed 6 3 5 on squats; FP (full plus partial ROM) performed 3 3 5 on squats and partial squats. zF performed 6–7 3 3 on squats; FP performed 3 3 3 on squats and partial squats (Bazyler. 2014).

Each training session began with a dynamic warm-up followed by warm-up sets on squat. The F group performed full squats only, whereas the FP group performed full squats followed by partial squats (from 100° knee angle to lockout position).

• 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). 

To assess the effects of the training manipulation, the researchers assessed anthropometrics, 1RM squat, 1RM partial squat, dynamic and isometric strength at the beginning of weeks 4 and 12 dynamic testing sessions.

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).

As you can see in Figure 1 the researchers did measure significant differences with respect to the increase in 1RM on both the full squat (FP), only, and the full + partial squat group - albeit without significant inter-group differences. Inter-group differences were obvious, however, for the  allometrically scaled isometric squat peak performance, where the specificity of the exercise is reflected in the difference between the peak performance at different positions, with

• 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,

an observation that would not exactly warrant the scientists conclusion that "[p]ractically, partial squats may be beneficial for strength and power athletes during a strength-speed mesocycle while peaking for competition" (Bazyler. 2014).

Figure 2: Changes in impulse scaled at 90° and 120° knee-angle (Bazyler. 2014).

Against that background it is actually quite surprising that the changes in the scaled impulse at 90° and 120° was significantly larger in the full + partial squat (FP) group for both angles. In physics the impulse is the integral of a force with respect to time, which implies that the overall force the trainees in the FP group were able to apply to the bar over a certain time period was larger at both 90° and 120°, in spite of the fact that the isometric peak force was lower at 90°.

"That's not 90°, yet. Go deeper, if you want to see results!"

Bear in mind: We are not comparing full ROM to partial ROM training. This comparison has been done by McMahon et al. one year ago and as you, as a loyal SuppVersity reader know, the results of their realistic 8 weeks leg training + 4 weeks detraining program shows that "Full ROM = More Growth, More Strength, More Structural Changes & More Sustainable Gains & Fat Loss" | learn more.

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!).

Practically speaking this is a significant advantage, because the guys in the FP group would be less likely to "die" at the dead point of the squat exercise at 90° - it's after all not the isometric peak force, but a "constant" force that is applied for an extended period of time that's required to move the bar up (the peak force would matter for exercises like jump squats).

Figure 3: changes in force-time curve with training (Bazyler. 2014)

I guess this advantage will become even more obvious if you take a look at the changes in force-time curve with training in Figure 3, where the orange curve represents the full squat, only, and the orange curves the full + partial (FP) squat groups.

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)

Similarly, the researchers observed strong correlations between 1RM squat and IPFa at a knee-angle of 90° (r = 0.72, p < 0.001), and moderate correlation at the higher position of 120° (r = 0.45, p = 0.005), as well as a moderate correlation between the change in IPFa 90° pre- to postintervention and full ROM squat and the total work load (r = 0.42, p = 0.048).

Suggested read: "You Want Maximal Performance & Size Gains + Complete Thigh Development? Then Full Squats are For You!" | learn more.

Bottom Line: Overall the results of the study at hand do suggest that the addition, not the replacement of full with partial squats may offer significant benefits to previously strength trained individuals, if their goal is not solely to increase their 1-RM, where the difference of 1.6% did not reach statistical significance in the course of the 7-week resistance training intervention.

As the authors point out, though, "the larger relative training intensities accomplished by the FP group during the final 3 weeks of training suggests superior adaptations" (Bazyler. 2014). In conjunction with the previously discussed advantages with respect to the overall rate of force development, the findings do thus "support previous claims that partial plus full ROM training is an effective strategy for improving maximal strength in subjects with previous strength training experience" (Bazyler. 2014) | Comment on FB.

References:

• 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.

Training for Size & Strength - Does the Rest Matter? Study Finds 7-9% Greater Increase in Muscle Size With Decreasing Rest Periods.

Image 1: If you want to build Arnold-esque arms you better not sit around too long in-between your sets.

"Short rest periods to burn fat, medium rest periods to build muscle and long rest periods to build strength" - it's actually pretty likely that one of your trainers, gym buddies or fatherly mentors told you something along those lines in the past. In view of the results of a soon to be published international study by Brazilian researchers from the State University of Campinas and the Federal University of Rio de Janeiro and their American colleagues from the Eastern Illinois University, the University of Memphis and the Colorado College (Souza-Junior. 2011), this is probably the next item on list of widely accepted bodybuilding myths that have a spark of truth to them... at least for recreational strength trainees who use some creatine monohydrate to promote their strength and mass gains.

Learn more about muscle builder & fat shredder training at the SuppVersity

Optimizing Rest for Size and Strength Gains

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For their study, the results of which are going to be published in the next issue of the Journal of the International Society of Sports Nutrition, Tacito P. Souza-Junior and his colleagues recruited 22 "recreationally trained" men with a minimum of one year resistance training experience at a frequency of 4 sessions a week, who were randomly assigned to one out of two exercise protocols, which differed only in the time the subjects were allowed to rest in-between sets (cf. figure 1).

Figure 1: Identical training protocol for all subjects participating in the study (compiled based on information from Souza-Junior. 2011)

The only difference between the groups was that half of the subjects trained with a constant rest time of 2 minutes between sets over the whole 8 weeks (CI group), while the remaining subjects had to decrease their rest times from week to week (DI group) according to the scheme illustrated in figure 2. The training sessions were supervised and the subjects were " verbally encouraged to perform all sets to voluntary exhaustion". Considering the overall workload and the training frequency, this were probably pretty hard weeks for the 22 trainees.

Figure 2: The rest times decreased according to a standardized protocol by 15 sec each week.

In addition all subjects, who btw. did not follow a standardized diet, consumed the proven creatine + maltodextrin mix (7 day loading phase with 20g/day creatine + 20g maltodextrin followed by a maintenance dose of 5g creatine + 5g maltodextrin taken immediately post workout) that has been used in numerous studies before.

Figure 3: 1RM performance (in kg) for bench press and barbell squat before and after the 8-week training period in subjects with constant and decreasing rest periods (data adapted from Souza-Junior. 2011).

Now, if the initially stated "wisdom" held true, then the 11 subjects with constant rest periods should either have gained more muscle (if you consider 2 minutes a "medium" rest period) or built more strength (if you would say that 2 minutes belong to the realm of "long" rest periods) - yet figures 3 and 4 seem to indicate that neither of that was the case.

Figure 4: Muscle CSA (in cm²) of arm and tigh muscles before and after the 8-week training period (data adapted from Souza-Junior. 2011).

If we have do yet a closer look at the effect sizes, there is yet a notable advantage of the DI protocol in terms of the measured increases in muscle CSA with +14% and +19% in arm and tigh CSA in the constant rest interval group (CI) and +21% and +28% in the decreasing rest interval (DI) group.

SuppVersity Classic: Full ROM = More Growth, More Strength, More Structural Changes & More Sustainable Gains & Fat Loss - Insights from Realistic 8 Weeks Leg Training + 4 Weeks Detraining | more

There is a spark of truth to every myth To give you an idea of how significant - and I am talking about "posing significance" not statistical significance here - this is, I have calculated the respective increases in arm- and tigh-circumference, which would differ by 0.4cm and 0.7cm, respectively. Not really outstanding, but nevertheless an important finding of which the researchers say that it lends support to the notion that

decreasing [rest] interval[s] seems to be more efficient than constant interval to produces [sic!] hypertrophic responses.

It has yet to be stated that the 11 subjects in the decreasing rest interval group paid dearly for this increase in muscular hypertrophy, as their "exercise performance" as measured by the total workload per session decreased profoundly from week 1 to week 8: -35% total volume for barbell squats and -30% for bench presses.

The subjects who used constant rest periods, on the other hand, increased their total volume by +20% for squats and by +30% for bench presses. That being said, all powerlifters out there better stick to their constantly (long) rest periods if they do not want to compromise their game.

High Reps vs. 5x5 - Revisiting the "High(er) Reps for Fat Loss"-Myth: Do You Really Believe that "Burning" +13 Extra Calories Will Make a Difference?

Image 1: Vince Andrich, here at the 1988 Nevada State Bodybuilding Competition, knew it all along: Hard work, not high reps will get you the stage-ready physique everybody aspires... and I mean look at him are you seriously questioning Vince's expertise?

If you have listened to the latest installments of BodyRX Radio, the idea that strength (and HIIT) training, not calorie restriction and endless cardio sessions pave the way to a leaner, more muscular physique. And although it may be of secondary importance whether you are burning 100kcal or 200kcal during those workouts, it stands out of question that you won't get rid of those damn spare tire, if you do not exert yourself in the gym (something Layne Norton is notorious for, as you may have seen in one of his workout videos or heard on BodyRX, lately) - because, after all, energy expenditure does count, even if the energy equation is much more complex than the simplistic calories in vs. calories out paradigm that is still upheld by mainstream dietitians. The results of a recent study from scientists from the Departments of Health and Sport Sciences at the Salisbury University and the University of South Carolina are may thus come handy to decide, to which extent workout intensity and volume influence acute and post-exercise energy expenditure (Mazetti. 2011). Or, to make it simple, does the good old bro-scientific high volume, high rep, low-weight training during a contest prep make any sense at all?

Exposed! The absurdity of going to the gym to "burn calories"

Scott A. Mazetti and his colleagues recruited 10 resistance trained young men (22+/-3.6 years) with an average body mass of 84+/-6.4kg, a height of 180+/-5.1cm, and a body fat percentage of 13+/-3.8% - an adequate model of the "average gymrat", if you asked me. After a 3-week familiarization and testing period, all participants performed every of the following four different explosive strength training regimen in a randomly assigned, but counterbalanced order (cf. figure 1)

Figure 1: The four training protocols all trainees performed after an initial 3-week familiarization and testing period in a randomly assigned, but counterbalanced order (Mazetti. 2011)

Now, you may complain that there is neither a "high rep" nor a "heavy group" in the conventional sense of 15+ pump training with an endless amount of sets, or the minimalist 1-2 rep approach of the hardcore HIT faction... granted, you are right. Nevertheless, we should see a significant difference in energy expenditure between a 5x5 and a 4x10 (both normally considered as "hypertrophy training) regimen, already, if the good old saying "high(er) reps" for increased energy expenditure and subsequent fat loss had any merit.

Figure 2: Energy expenditure (kcal/min) during and after squatting, and bench pressing in the four training groups and total energy expenditure during the whole workout and 60min post-workout window (data adapted from Mazetti. 2011)

As figure 2 goes to show, there are differences in energy expenditure between the different protocols, during the squat, the deadlift and up to 5 minutes post exercise, nevertheless, the "the differences in total energy expenditure among protocols were not significant". So, even if there were any merit in exercising primarily to burn calories during your workout (a ridiculous way of trying to lose weight, which is predestined to fail, anyway), the -6kcal difference between the -13kcal difference between the least energy consuming form of training, i.e. 5x5 and the one with the highest energy demand, i.e. 4x10, would not even suffice to "make up" (another hilarious idea) for proverbial "apple à day", which keeps the doctor away.

Image 2: Don't let your lazy love handles decide what type of "cardio" you are doing!

A brief note on what Lane already pointed out in the last installment of Body RX Radio: Classic low-intensity cardio training may "burn" calories for a week or two. Afterwards, this type of chronic low-grade stressor is yet notorious for shutting down your metabolism and reducing your resting energy expenditure. Of high intensity aerobic exercise with intensities way beyond the 70% VO2max limit (YES! This is aerobic, two - cf. "HIIT is the Hit! Even for Patients with Myocardial Infarctions!"), we have known for decades that it increases your resting energy expenditure by "5 ±15% for 24 ± 48 h" (Hunter. 1998). So, I suggest you get off the stationary bike you are just riding while browsing the web, get your running shoes out and do a couple of sprints. Your spare tire won't like that, but I bet you will like the effect it's going to have on the person you see in the mirror, each morning ;-)

In view of these results, it appears prudent to reassess the often-heard advice of doing high reps for fat loss. Even if you insist that you need to "burn calories" in the gym, it is very unlikely that those few extra calories would make a noticeable difference in terms of how you look on stage - or just in front of your private mirror. Moreover, even this small advantage vanishes as soon, as you increase the workload by doing 2x7 + 2x6 with a heavy weight, or put simply: Identical workload identical calorie expenditure.

When Rodents Squat, Scientists Gain Insights into How Muscles Grow. IGF-1 Response to Exercise Does Matter - Locally, not Systemically, of Course!

You want to build big wheels? Look no further get yourself the "Squat T-Bar" with integrated 15mA electrical 'motivator' (Aguiar. 2012)

"A rodent study investigating strength workouts?" Yeah, I know it does not sound like that would be in any ways news-worthy, but if you take a look at the image on the right, you will immediately realize: This study is different! Instead of using a treadmill or simply stitching down (or rather up) one of the hindlimbs of the rodents to induce a chronic overload on the other one (don't laugh, many rodent studies have done just that), the study at hand (Aguiar. 2012), which is going to be published in the next issue of the International Journal of Sports Medicine, used a not innovative, but unfortunately largely forgotten (or overlooked?) torturing device that has been developed by Japanese researchers roughly 20 years a ago (Tamaki. 2012).

The rodent torture... ah pardon squat rack ;-)

After being fitted with a canvas jacket in a way that would enable the researchers to limit the twisting and flexion of their torsos (no, that was not a weight lifting belt ;-), the 32 male Wistar rats (80 days old, 250–300 g) were suspended in a standard position on their hind limbs and "encouraged" to exercise by "electrical stimulation [...] that was applied to the rat’s tail through a surface electrode"  (Aguiar. 2012).

Using their neat little toy, the eight researchers from the University Estadual Paulista, in Botucatu, Brazil, were able to submit the rats to a relatively realistic progressive resistance training regimen for either 8 or 12 weeks. Three times per week each rodent had to do 4 sets  of squats for 10-12 repetitions at 65-75% of its individual 1-RM (maximal weight the rodent could handle). During the study period, Aguiar et al. adjusted the weights twice a week to ensure the same training intensity throughout the experiment (something I would highly recommend to anyone of you, as well; try to pack on 1.25lbs - 2.5lbs at least every other week).

Figure 1: Body weight, muscle weight (plantaris, only) and food intake relative to body weight of the control (C8, C12) and trained (T8, T12) rats before and after the 8-week (C8, T8) and 12-week (C12, T12) intervention (data adapted from Aguiar. 2012)

As you can see in figure 1, this minimalist approach to leg training lead to an increase in both body weight and muscle weight that may initially look as if it was strongly linear. You do yet have to be careful about statements like that, because (a) the rodents did gain weight irrespective of whether they were training or not (80 day old rats are still growing!), so comparing the four bars next to each other and saying "yep, linear!" is not feasible, because this would mean linear as in not training for eight weeks < training for 8 weeks < not training for 12 weeks < training for 12 weeks, which is obviously nonsensical. That being said, there is simply (b) insufficient data to say anything about the linearity -- after all, we do have only three data points per group.

"All groups started the experiment with similar body weight. There was a significant increase (p < 0.05) in the body weight of the 4 groups in the resistance training program (C8: 35.5 %; T8: 27.7 %; C12: 46.9 %; and T12: 40.1 %) and final body weights were not significantly (p > 0.05) different between groups. Furthermore, no significant (p > 0.05) differences in the weekly food intakes were observed between the groups."(Aguiar. 2012)

What does yet stick out, is that the obviously age-dependent weight gain in the control groups C8 and C12 did not increase the weight of the plantaris muscle to a weight anywhere near to the muscle weight, the rats in the trained groups achieved.

Muscle gains and strength gains went hand in hand

In the rats who were subject to the three-times-per-week exercise regimen, on the other hand, those increases in muscle size went hand in hand with highly significant improvements in 1-RM squat power; While all groups had begun the training protocol with similar absolute 1-RMs of ~450g (that's about 130% body weight, pre) ...

"[...] training for 8 and 12 weeks promoted a significant (p < 0.05) increase in the RM/BW ratio in the T8 (pre- vs. post-training: 35.7 % increase, p < 0.05) and T12 (pre- vs. post-training: 57.1 % increase, p < 0.05) groups, while no statistical (p > 0.05) difference was observed in their respective control groups." (Aguiar. 2012)

Consequently, the ratio of 1-RM to body weight was 36.1 % and 57.7 % higher in the groups who had been training fot the last 8 or 12 weeks than in the lazy controls and the time-effect yielded another +22% increase in strength in those rodents who trained for 12 and not just 8 weeks.

Figure 2: Strength gains (left) and increases in cross sectional area, as well as intramuscular IGF1, myogenin and myoD expression (data adapted from Aguiar. 2012)

Now you may have heard all that before, what really makes this study stand out, however, is the observation of statistically highly significant correlations of intra-muscular IGF1, myogenin and myoD  mRNA expression, which speaks in favor of my previous hypothesis (read up on that in the Intermittent Thoughts on Building Muscle) that muscle growth is triggered, driven and maintained almost exclusively at a local level.

What are myogenin and myoD? Both are myogenic regulation factors with myogenin actually being part of the myoD family of transcription factors that will make stem cells develop into myocytes (myo D is highest in recently activated satellite cells).

So, when you are looking for "hormonal" (or other pro-anabolic) ghosts (Phillips. 2012), it is imperative to look for them right where the spook, or, in this case, the muscle building magic happens. If you do just that (see figure 2) and correlate the intra-muscular mRNA expression of IGF-1, myogenin and myoD, you will find the "ghostly" explanation for strength and size gains, as well as the confounding structural changes in the architecture of the muscle, with corresponding correlations between the increases in muscle cross-sectional area (CSA) of r = 0.85 (p = 0.0001), r = 0.87 (p = 0.0001) and r = 0.88 (p = 0.0001) for myoD, myogenin and IGF-1, respectively.

Fiber type changes take their time and occur only within the type II spectrum

A neat side-finding, which is actually no news, though, pertains to the fiber-type conversions that took place in response to the exercise regimen. Firstly, the scientists confirmed the notion that these changes occur exclusively within a certain fiber type. In other words, while Aguiar et al. observed conversions from the metabollically more flexible type IIX/D to the highly glycolytic (power) IIA type, no conversions of the highly oxidative type I to type II fibers were observed. And though the results would generally suggest that fiber IIX/D-to-IIA type conversion, as they 

"[...] also appear to occur during endurance training in humans, so that it would [be] reasonable to think that any exercise stimulus (e. g., endurance or strength) that is sufficient in duration and/or intensity can potentially induce conversions within the fast fiber population from type IIX/D to type IIA" (Aguiar. 2012),

the time-frame in the course of which these changes took place -- namely 12 weeks -- would confirm that the common fear of strength and endurance athletes could provoke negative structral adaptations from doing a "cardio" or "strength" workout from time actually is actually unwarranted. Neither will the former turn a powerlifter into a weakling, nor will the latter make a marathon runner "bulky". Both powerlifter and marathoner are on the contrary going to benefit from the conditioning effect and increase in strength, respectively -- not to mention the important effects on overall health both and not as mainstream stupidity will tell you only the powerlifter can derive from, figuratively speaking, "killing some game in the other's territory"

Bottom line: More food for intermittent thoughts on building muscle ;-)

Figure 3: Correlations between acute GH (A), free testosterone (B), IGF-1 (C)  and cortisol (D) responses (area under the curve—AUC) and gains in type II fibre CSA (Burd. 2012).

Eventually, this study is an excellent example of a way to design a rodent study in a way that will render its results actually meaningful. And what's more, in this particularly case these results are not just meaningful, but can also help us to make some sense of a couple of things we have not fully understood / appreciated, as of yet.

What I am particularly thinking about here, is the contrast between the in-vitro effects of IGF-1 and the (more or less absent) real-world effects of the IGF-1 response to exercise (=systemic increase), as it was observed by West and Phillips in a 2012 study. In their well-powered longitudinal study, neither the acute increase in systemic testosterone, nor the exercise induced increases in systemic IGF-1 showed significant correlations with the gains in type II CSA in a cohort (n = 56) of young men in response to 12 weeks of resistance training (West. 2012; see figure 3).

Another interesting finding of the West study was that, contrary to the circulating testosterone and IGF-1 levels, GH and cortisol did show direct correlations with increased muscle cross sectional areas in type II fibers.

And while the former correlation may be explained by the influence of growth hormone (GH) on the local expression of IGF-1 (Hameed . 2004), there is another open question left: How does cortisol actually figure in here? I mean, the chronic elevation / exogenous adminstration of cortisol, has been show to do the exact opposite, i.e. it decreases the local IGF-1 mRNA expression (Inder. 2010).

Figure 4: Graphical summary of what you should have learned Intermittent Thoughts on Building Muscle ... you didn't 'cause you are new to the SuppVersity or simply forgot about it? No problem read the preliminary summary and browse the individual chapters here!

What was missing in the Inder study, however, was the exercise component: Working out does not just exert protective effects against the negative side effects of the provision of exogenous "cortisol" (in this case Dexamethason), as they were observed in the afore referenced study by Inder et al., exercise will also lead to profound increases in local IGF-1 mRNA expression (e.g. +60% in Bamann. 2001), despite the fact that it will also increase the release of the falsely vilified anti-inflammatory glucocorticoid, cortisol... acute vs. chronic, local vs. system, peak values and amplitudes vs. plateaus and AUC values - you got to keep all these contrastive, yet complementary pairs in mind, when you are thinking about the endocrine and intracrine (within the cell) mediators of skeletal muscle hypertrophy.... what? Sounds familiar? Well, you must have been following the Intermittent Thoughts on Building Muscle, then ;-)

References:

• Aguiar AF, Vechetti-Júnior IJ, Alves de Souza RW, Castan EP, Milanezi-Aguiar RC, Padovani CR, Carvalho RF, Silva MD. Myogenin, MyoD and IGF-I Regulate Muscle Mass but not Fiber-type Conversion during Resistance Training in Rats. Int J Sports Med. 2012 Oct 11.
• Bamman MM, Shipp JR, Jiang J, Gower BA, Hunter GR, Goodman A, McLafferty CL Jr, Urban RJ. Mechanical load increases muscle IGF-I and androgen receptor mRNA concentrations in humans. Am J Physiol Endocrinol Metab. 2001.
• Ding H, Gao XL, Hirschberg R, Vadgama JV, Kopple JD. Impaired actions of insulin-like growth factor 1 on protein Synthesis and degradation in skeletal muscle of rats with chronic renal failure. Evidence for a postreceptor defect. J Clin Invest. 1996 Feb 15;97(4):1064-75. 
• Inder WJ, Jang C, Obeyesekere VR, Alford FP. Dexamethasone administration inhibits skeletal muscle expression of the androgen receptor and IGF-1--implications for steroid-induced myopathy. Clin Endocrinol (Oxf). 2010 Jul;73(1):126-32.
• Phillips SM. Strength and hypertrophy with resistance training: chasing a hormonal ghost. Eur J Appl Physiol. 2012 May;112(5):1981-3-
• Sculthorpe N, Solomon AM, Sinanan AC, Bouloux PM, Grace F, Lewis MP. Androgens affect myogenesis in vitro and increase local IGF-1 expression. Med Sci Sports Exerc. 2012 Apr;44(4):610-5.
• Tamaki T, Uchiyama S, Nakano S. A weight-lifting exercise model for inducing hypertrophy in the hindlimb muscles of rats. Med Sci Sports Exerc. 1992 Aug;24(8):881-6.
• West DW, Phillips SM. Associations of exercise-induced hormone profiles and gains in strength and hypertrophy in a large cohort after weight training. Eur J Appl Physiol. 2012 Jul;112(7):2693-702. 

Bicarbonate For Strength Athletes: 25g of Baking Soda Up Your Squat (+27%) & Bench Press (+6%) Within 60 Min

NaHCO3 probably won't make the burn go away, but it will help you push though it.... and no(!), you don't have to be afraid to retain water - sodium bicarbonate is actually going to lower aldosterone and is thus - if anything - going to have a diuretic effect (Musabayane. 1991). Calcium loss etc. is nothing you have to be afraid of either (Luft. 1990).

After yesterday's astonishingly popular excursion into dating sciences, we are back to "normal" or as others would call it "extraordinary", here at the SuppVersity today ;-) And to make really sure you know that you're right here we're going to get back into the ergogenic groove with one of my personal favorites: Sodium bicarbonate, NaHCO3 or as your granny calls it, baking soda!

In the unfortunate case you have no idea, what I am taking about, I'd suggest you briefly go through the previous SuppVersity articles and Facebook posts (e.g. +13% increase the sprinting capacity; sorry for the → typo) about the ergogenic effects of baking soda . Once you've done that it should not really come as a surprise that scientists from the real Human Performance Laboratory  at the Coventry University in the UK found that NaHCO3 will not just for cyclists, runners and rowers, but also for "bench pressers" and "squatters" ;-)

One thing after the other, though!

If you know your SuppVersity articles by heart, you are probably thinking about the Kerr study from September 2012, now - right? For the average gymrat, this was probably the most exciting paper on the ergogenic effects of sodium bicarbonate supplementation I've written about (see "22g Baking Soda 60min Before a Old-School 4 x 12RM Leg Workout Allow for a 22 Rep Volume Increase on Hypertrophy Oriented Squat + Leg Press + Leg Extension Quads Routine" | read more).

A note for those with gastrointestinal problems or an insurmountable gag reflex: I know that downing 25g sodium bicarbonate at once can be disgusting and sends people with weaker stomachs right to the toilette. Fortunately, a 2012 study by Dreher et al. suggests that "serial loading" with several smaller servings of baking soda works at least as well | learn more

And while the Kerr study was among the first to demonstrate significant beneficial effects of sodium bicarbonate in a strength training scenario, it is - if you come to think of it, actually not that surprising to see that the H+ (=hydrogen ions → acidity) buffering effect works just as well during a high volume leg workout, as it does, during high intensity cycling and sprinting [just a note on the H+ buffer: contrary to beta alanine, bicarbonate buffers the acidity in the blood, not within the muscle cell and will thus have greater effects on the periphery than carnosine the histidine + beta alanine dipeptide you are actually looking for, whenever you take your beta alanine supplement.

Now while it may not have been surprising that high volume + baking soda does make a perfect match, it is, as you will hopefully agree, not exactly straight forward that we would see similar benefits on the low volume performance test, the 8  men (mean age, height and body mass → 20  ±0.9 years, 1.8  ± 0.1m and 78.4  ± 15.6kg, respectively)  who had been recruited for the study at hand had to perform.

Three sets of squats and bench presses? Isn't that too little volume for NaCO3 to work?

All the participants who had at least one year of strength training experience competed  in  team  games  (rugby  union,  soccer, basketball) at the national level and were concomitantly training more than 10 hours per week as part of their regular preseason preparations (those included 3h of resistance training). During the testing conditions to which the subjects had been randomly assigned, all of the performed

Learn about the best chest exercises in the SuppVersity EMG Series.

• three sets of bench presses to failure at 80% 1RM, and 
• three sets of back squats "to failure" at 80% 1RM

With three minutes of rest between the sets and five minutes of rest between exercises, this is, as I already mentioned, not exactly the workout you would usually expect to benefit (most) from bicarbonate supplementation. Still, the data in Figure 1 tells another story:

• 0.3g/kg NaHCO3 in 5 ml/kg of artificially sweetened water (NaHCO3), instead of
• 0.045g/kg NaCL in an artificially sweetened water drink matched for taste

60 minutes before the two blinded performance tests did the trick - it did increase the mean total reps for squats (+6.7 reps; +27%) and bench preses (+1.5 reps; +6% -- note: I used the values from the table in the full text. They differ from those in the abstract according to which the performance increase would be 7%)

Figure 1: Back squat and bench press performance in three subsequent sets (Duncan. 2013)

As it was to be expected due to the low volume and long rest between sets, there was no significant change in blood lactate across time or between conditions. There were however treatment × time interactions for blood pH (p = 0.014) and blood HCO3 concentration (p = 0.001), with the increasing pH and bicarbonate (HCO3) levels in the blood of the NaHCO group being the obvious cause of the highly significant performance benefits.

Does beta alanine hamper instead of improve your sprinting performance? Learn more in a previous SV Article.

Baking soda for strength athletes: After the previously cited study by Kerr et al. this is study #2 to prove that the usefulness of baking soda, sodium bicarbonate or NaHCO3 (call it whatever you want) is by no mean, as it was long thought to be, restricted to endurance sports with intermittent sprints. With the study at hand there is enough evidence to believe that it's acute effects are going to be present whenever you're pushing yourself to your own limits and in view of the fact that pushing to the limits, in order to raise the bar is what's driving progress.

I would therefore be curious to see a long(er) term study (8-12 weeks) taking a look at the cumulative benefits of sodium bicarbonate supplementation on strength and mass gains in trained and untrained individuals. Unfortunately, I suppose that no one with the money to finance that study will share my interest. In the end, a study like this would after all entail the risk of exposing how pathetic the 2.85% performance increase we see in the average beta alanine study actually are (Hobson. 2012).

Reference: 

• Duncan MJ, Weldon A, Price MJ. The effect of sodium bicarbonate ingestion on back squat and bench press exercise to failure. J Strength Cond Res. 2013 Oct 11. [Epub ahead of print]
• Hobson RM, Saunders B, Ball G, Harris RC, Sale C. Effects of β-alanine supplementation on exercise performance: a meta-analysis. Amino Acids. 2012 Jul;43(1):25-37. 
• Luft FC, Zemel MB, Sowers JA, Fineberg NS, Weinberger MH. Sodium bicarbonate and sodium chloride: effects on blood pressure and electrolyte homeostasis in normal and hypertensive man. J Hypertens. 1990 Jul;8(7):663-70.
  
• Musabayane CT, Balment RJ. Renal effects of aldosterone in the sodium bicarbonate infused rat. Ren Fail. 1991;13(2-3):71-6.