Aerobic and Anaerobic Energy Costs of Strength Training: Single Set of Squats More Demanding than Bench Press, Triceps Extensions and Lat Pull Down Together!

Image 1: The squat - as intense as it is, it is no replacement for "aerobics"; more on squatting in the EMG Series

As a diligent student of the SuppVersity you will obviously remember yesterday's news on the potentially detrimental chronic increases in cortisol, Kirschbaum et al. (Kirschbaum. 2011) have observed in a group of 304 amateur endurance athletes. This raises the question, whether or not your 3-4 strength training sessions per week would not suffice as "aerobic exercise" - after all, most people are huffing and puffing much more after one sets of squats than after 45 min. on a recumbent bike. And even if you were not interested in increasing your aerobic performance, I assume it would be nice to know if squats really are so energetically intense as they feel, or, in other words, how much more energy you are expending doing squats vs. let's say triceps extension ;-)

And more generally, i.e. in view of the aerobic effect and energy expenditure in the course of a complete strength training session, it would be interesting to know, ...

1. how much total energy you were expending while benching, squatting, rowing and co., and
   
2. what the relation of aerobic to anaerobic energy expenditure was like during heavy resistance training.

Both questions have been a subject of scientific debates for quite some time. The measurement of blood lactate levels, as well as other methods to access total energy expenditure, the ratio of aerobic to anaerobic metabolism and the highly controversial contribution of increased energy expenditure after resistance training (EPOC) have been questioned lately (Robergs. 2007). Reason enough for Jefferson M. Vianna and his colleagues from Brazil and Portugal to take another, closer look at the total and relative energy costs of resistance training (Vianna. 2011), in order veri-/falsify previous empirical data.

As their measuring tool of choice, the scientists selected the oxygen deficit method (AOD), where the anaerobic contribution to the overall energy expenditure is estimated by linear extrapolation of the VO2 at supra-maximal intensities and the AOD is then calculated by subtracting the cumulative oxygen uptake (VO2Ac) from the estimated energy demand. As the scientists point out, thus...

[...] the VO2Ac represents the portion of energy obtained by aerobic processes and the AOD represents the portion of energy obtained by anaerobic processes [so that] their sum equals the total VO2 during exercise.

The subjects in the Vianna study were 14 male resistance trainees (26.6 ± 5.4 years, 1.77 ± 0.07 m height, 80.1 ± 11.4 kg body mass and 11.2 ± 4.6 % body fat) with at least one year of training experience on a protocol with three or more training sessions per week. After height, weight and several skin fold measures (chest, mid-axillary, tricipital, sub scapular, abdominal, supra iliac, and thigh) had been taken, the individual 1RM max for bench press, half squat, lat pull down and triceps extension were assessed. Afterwards, the scientists measured the VO2 for each of the four exercises at 12% and 20% of the previously established 1RMmax. The same procedure was repeated 48+h later at 16% and 21% of the individual 1RM max. Eventually (again 48+h rest), the subjects had to perform their bench presses, half-squats, lat pull downs and triceps extension at 80% of their 1RM. The gas the subjects expired during those sessions was collected and recorded by an open air circuit analyzer - you can see part of the results plotted in figure 1.

Figure 1: VO2Ac (ml/kg) and accumulated oxygen deficit (AOD; ml/kg) at 80% 1-RM for bench press, half squat, triceps extension and lat pull down (data adopted from Vianna. 2011).

If you recall what the scientists said about the interpretation of VO2Ac and the accumulated oxgyen deficit (AOD), it is pretty evident that there is a reason, why many trainees fear the the squat. After all, the "king of all exercises", as it is commonly referred to, has by far the highest total (cf. figure 1), as well as relative (cf. figure 2) anaerobic component of all four tested exercises.

Figure 2: Relative contribution of aerobic and anaerobic metabolism to overall energy costs of bench press, half squat, triceps extension and lat pull down at 80% of the individual 1RM (data adopted from Vianna. 2011).

Despite inter-individual variations this supremacy of the squat is statistically significant (p<0.05, indicating chances that this was an incidental observation are <5%).

Figure 3: Total energy demand (ml/kg) of bench press, half squat, triceps extension and lat pull down at 80% of the individual 1RM (data adopted from Vianna. 2011).

If we finally take a look at the total energy demands, the underlying reason for your panting becomes even more evident: Squatting is 3.3x more energetically demanding than bench pressing or doing triceps extensions or lat pulldowns.

The "king of all exercises" is in fact so energetically demanding that one set of squats at 80% of your 1RM max will still expend ~9% more energy than a workout consisting of bench presses, triceps extensions and lat pull downs! Nevertheless, while it cannot be excluded that squatting will indirectly improve your aerobic exercise performance, as well, in and out of itself, none of the tested exercises is suitable to replace what is commonly understood to be "aerobic" or "cardio training" - but hey, in view of what I have posted about the effects of HIIT training, lately, doing (regular) "cardio" training may be obsolete, anyways ;-)

Lat Pulldowns Revisited: What's the "Optimal" Grip Width? A Medium Grip Excels - In Spite or Due to the Increased Biceps Activation? Plus: Harder ≠ More Effective

Building Wings: Is it really about proper grip width or are effort and genetics the real determinants of your wing-size?

As a SuppVersity reader you will be well aware that the term "optimal" in conjunction with grip width will always be goal-specific. It is, for example, well possible that you would have to use completely different grips to "optimally" train the posterior chain of the rotator cuff muscle and your lats and the  results Vidar Andersen and his colleagues from the Sogn og Fjordane University College, the Norwegian University of Science and Technology and the Hysnes Rehabilitation Center at the St. Olavs University Hospital present in their latest paper in the Journal of Strength and Conditioning Research could help us to find out which grip widths these are (Andersen. 2014).

While the researchers point out, "the effects of pronated grip widths in the anterior lat pull down are not yet fully determined" (Andersen. 2014), Suppversity readers know better. There is actually conclusive evidence from a study by Boeckh-Behrens & Buskies I discussed at length in the SuppVersity EMG Series that an optimal stimulation of the latissumus dorsi is achieved with a shoulder-wide and thus probably 10-15 cm narrower overhand grip; and not with the popular "grip-as-far-apart-as-possible crucification" grip generations of bodybuilders considered the "optimal wing builder."

Even though it's more difficult (you can handle less weight), the wide grip is not necessarily more effective.

Individuality counts & difficult does not equal effective: In view of interpersonal differences and the fact that it is, much contrary to popular believe, not the exercise or way to execute a certain exercise that hurts the most, which is most effective, it is well possible that the previously mentioned "generations of bodybuilders" were right and the extra-wide grip gave them their impressive wingspan. It is yet equally possible that they fooled themselves into believing that this was the most effective way to perform the exercise due to the "good pain" they (mis?)interpreted as a signal of optimal muscle stimulation.

I am not sure, whether or not Andersen et al. even know the said study, the results of which have only been published in German. What they do know, though, are the results of a similar, yet small-scale study by Lusk et al. with methodological issues- e.g.:

• assessment of only two grip widths, 
• no familiarization session before the 1RM test, 
• same absolute rather than relative load in all the different grips, and 
• sets were not performed until or close to failure

As the Swedish researchers rightly point out, the two latter "methodological limitations make it difficult to transfer the findings to real life training" (Andersen. 2014). To underline the validity of this claim, the scientists cite a set of studies by Saeterbakken et al. (2011-2013) to substantiate the hypothesis that using equal relative loads when comparing different exercises is a prerequisite for a reliable comparison of different exercises and exercise modalities.

Optimal research design for optimal grip width investigations!?

Accordingly, a within-participant repeated-measures design was used to examine the relative 6RM strength and concomitant EMG activity in anterior lat pull-down using narrow, medium, and wide
pronated grip widths, defined as 1, 1.5, and 2 times the biacromial distance (BAD), respectively (see Figure 1).

Figure 1: Photo illustrating the different grip widths used in the study at hand (Andersen. 2014)

As Andersen et al. point out, "the participants took part in 1 session approximately 1 week before the experimental test to familiarize the participants with the procedures and identify the 6RM load for the different grip widths." For the test, the exercise order was randomized and counterbalanced for each participant and was identical in the habituation and experimental tests.

In the study referenced in the SuppVersity EMG Series, it's the underhand shoulder- wide grip which produces a maximal activation of the latissumus dorsi - the wings, so to say | learn more

"To simulate a set in a typical workout, the participants performed a 6RM test (Pollock. 1998, Bird. 2005, Kraemer. 2004), which corresponds to approximately 85% of 1RM (Baechle. 2008) and is a recommended intensity for increasing muscle strength and hypertrophy (American College of Sports Medicine. 2009, Peterson. 2004).

By using equal relative load for each exercise with heavy loads performed to volitional failure, we can assess the practical significance of how the independent variable, grip width, affects the dependent variable, muscle activation." (Andersen. 2014)

Thus, the scientists hope to produce practically relevant results, which would make an "important" contribution to the "knowledge for athletes and coaches" (Andersen. 2014) -- and in view of the fact that their subjects were 16 healthy (age, 24 years; body mass, 81 kg; stature, 180 cm) with 6 ± 3 years of resistance training experience the latter, i.e. practical relevance, may actually have been achieved.

Figure 2: Normalized electromyographic activation of the concentric phase (left), and the eccentric phase (right) of the biceps brachii, latissimus dorsi, trapezius, and infraspinatus during 6RM in the lat pull-down performed with 3 different grip widths. Values are given as mean 6SD (Andersen. 2014)

Whether or not the same can be said of the differences you see in Figure 2 is yet (imho) questionable; and that not simply because of the negligible effect size, but also due to the fact that we still don't know how and if high EMG values of which we believe that they tell us something about the intensity of the muscular contraction are even associated with skeletal muscle growth and / or strength gains.

In their discussion of the results, Andersen et al. sidestep this issue and zone in on the quasi non-existent differences between narrow, medium, and wide pronated grips in the anterior lat pull-down, pointing out that a medium grip may still "have someminor advantages over small and wide grips", because - and this is a non-sensical assessment imho - "the biceps brachii had greater activity using a medium compared with a narrow grip in the concentric phase" (Andersen. 2014)

And while Andersen et al. are right and the overall activation of the latissimus dorsi does not appear to be significantly impaired by the increasing biceps involvement, it's still not exactly, what the previously referenced real trainer or trainee will be interested in.

Figure 3: If total time under tension (TUT | learn more) determined your gains, a medium grip would excel.

When all is said and done, we are thus - once again left with the ultimately valuable insight that it's not really worth to overthink the matter of "optimal muscle stimulation". The time you waste pondering the pros and cons of certain grip widths, of which you don't even know if their effects on the electromygraphical activation does even relate to their mass- and/or strength-building qualities, would be better spend actually doing lat pulls, or - even better - pull ups.

So what the f*** - What are you waiting for, the gyms and doorframes of the real world are waiting for you ;-)

References:

•  American College of Sports Medicine. "American College of Sports Medicine position stand. Progression models in resistance training for healthy adults." Medicine and science in sports and exercise 41.3 (2009): 687.
• Andersen, Vidar, et al. "Effects of Grip Width on Muscle Strength and Activation in the Lat Pull-Down." The Journal of Strength & Conditioning Research 28.4 (2014): 1135–1142 (in press).
• Baechle, Thomas R., and Roger W. Earle, eds. Essentials of strength training and conditioning. Human kinetics, 2008.
• Bird, Stephen P., Kyle M. Tarpenning, and Frank E. Marino. "Designing resistance training programmes to enhance muscular fitness." Sports medicine 35.10 (2005): 841-851.
• Kraemer, WILLIAM J., and NICHOLAS A. Ratamess. "Fundamentals of resistance training: progression and exercise prescription." Medicine and science in sports and exercise 36.4 (2004): 674-688.
• Lusk, Stephen J., Bruce D. Hale, and Daniel M. Russell. "Grip width and forearm orientation effects on muscle activity during the lat pull-down." The Journal of Strength & Conditioning Research 24.7 (2010): 1895-1900. 
• Peterson, Mark D., Matthew R. Rhea, and Brent A. Alvar. "Maximizing strength development in athletes: a meta-analysis to determine the dose-response relationship." The Journal of Strength & Conditioning Research 18.2 (2004): 377-382.
• Pollock, Michael L., et al. "ACSM position stand: the recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults." Med Sci Sports Exerc 30.6 (1998): 975-991.
• Saeterbakken, Atle H., Roland van den Tillaar, and Marius S. Fimland. "A comparison of muscle activity and 1-RM strength of three chest-press exercises with different stability requirements." Journal of sports sciences 29.5 (2011): 533-538.
• Saeterbakken, Atle Hole, and Marius Steiro Fimland. "Muscle activity of the core during bilateral, unilateral, seated and standing resistance exercise." European journal of applied physiology 112.5 (2012): 1671-1678.
• Saeterbakken, Atle H., and Marius S. Fimland. "Muscle force output and electromyographic activity in squats with various unstable surfaces." The Journal of Strength & Conditioning Research 27.1 (2013): 130-136.
• Saeterbakken, Atle H. and Marius S. Fimland. " Electromyographic activity and 6-RM strength in bench press on stable and unstable surfaces." The Journal of Strength & Conditioning Research 27.7 (2013): 1101–1107.
• Saeterbakken, Atle H., and Marius S. Fimland. "Effects of Body Position and Loading Modality on Muscle Activity and Strength in Shoulder Presses." The Journal of Strength & Conditioning Research 27.7 (2013): 1824-1831.16.