Ballistics Lunge Activates Muscle to the Same Extent as 34% Lighter Standardlift, Elastic Band & DBs Target Different Muscles. Plus: 10 Arguments for Explosives & Plyometrics

Lunge with resistant bands as it was done in the study (Jakobsen. 2012)

The paper the Danish researchers Jakobsen, Sundstrup, C.H. Andersen, Aagaard and L. Andersen are about to publish in one of the forthcoming issues of Human Movement Science is not the first certainly won't be the last study on explosive training (more) and plyometrics (more) you have and still will read about, here at the SuppVersity. And while I am not sure whether you would say that it is the most exciting one, I am pretty convinced that you will be inclined to hear how different rep-speeds (ballistic=explosive vs. normal) effected the EMG activity during a full-body exercise like lunges with different loads and equipment (dumbbells vs. resistant band).

Before we start, just a brief reminder for all of you who have not read the SuppVersity EMG series as of now. If you want to know the "best" exercises to target specific muscle groups, I'd suggest you make a detour to all or just those body parts you are interested in by clicking on the respective image in the "navigation" below:

Chest	Biceps	Back	Core	Legs	Triceps	Shoulders
Navigate the SuppVersity EMG Series - Click on the desired body part to see the optimal exercises.

Apropos, lunges were (unfortunately) not among the exercises the researches tested in the study the EMG series is based on. I personally consider them extraordinary valuable for whole leg development, and have to caution you that comparing squats to lunges on EMG basis is somewhat like comparing different types of red using black and white photos, because one of the main and in my humble opinion probably the most important argument against the significance of EMG measurements is that they tend to increase with the degree of weight you can move - this puts lunges in as much into a somewhat disadvantaged position as flys as a chest exercise and could lead to the misunderstanding that it would be better to perform 10 sets of squats than 5 sets of 5 for squats and 4 sets 10 for lunges as a legworkout. Especially if your goal is skeletal muscle hypertrophy, the latter is usually (you know there are no black-and-white solutions) the far superior choice.

Same activation with less load = training economy

That being said, the results of the Jakobsen study do still have their merit. After all, they clearly show that doing explosive or ballistic movements can provide diversion and new growth stimuli especially on those "auxilliary" exercises like lunges. In that, the lower overall weight can even come very handy as it should effectively reduce the risk of injury, which is - let's be honest - a very good argument not to do max. squats in a ballistic fashion, at all.

Figure 2: Normalized EMG activity during lunges with elastic bands and dumbbells (Jakobsen. 2012)

In fact, the EMG measurements, the scientists took while their subjects, 42 subjects (18 men, 24 women; age 41/45 years, BMI 24/25m²/kg, respectively), performed unilateral lunges with their dominant / preferred leg using either elastic bands or dumbbells (see image at the top of this article) to adjust the resistance, do actually confirm that training explosively, i.e. performing the lunge movement as fast as possible (ballistic contractions) does provide an increased contractive stimulus (Desmedt. 1977; Frost. 2008; Sakamoto. 2012), which will allow you to ellicit almost identical EMG activity as during controlled reps at a rep-speed of ~3s per rep with 34% less weight. Or as Jakobsen et al. have it:

"[...] ballistic lunges performed with high speed at medium loadings showed broadly similar EMG amplitudes as that seen during slower controlled speeds with high loading." (Jakobsen. 2012)

Furthermore, the "high-speed lunges" obviously took less time and reduced the effective workout time by 23%. Now, while this could be an advantage on days where you have only a very limited time-window to train the researchers argue that this will lead to an overall reduction in time under tension and thus training volume and should - depending on your training goals (my addition) - be compensated by increasing the training volume during power training by ~23 "to  achieve the same accumulated time under tension" (e.g. doing 10 instead of just 8 reps per set).

"Wait, there is something else: What about those hilarious resistance bands?"

Actually, the benefits of explosive/ballistic training are yet only one out of two interesting findings of the study at hand, after all it's likewise interesting to see how the use of those often derided resistance bands effected the EMG activity and other training parameters. So let's see, compared to lunges done with isoinertial loading (=dumbbells)...

• lunges with elastic bands showed an overall higher EMG activity, which also resulted in a slightly but significantly higher level of perceived loading on the Borg CR10 scale
• training with resistance bands elicited higher EMG activity in knee and hip extensor muscles (vastus lateralis, vastus medialis, rectus femoris, gluteus maximus) and during the more flexed knee joint positions (i.e., in the reversal phase)
• performing lunges with resistance bands added an non-linear element to the actual resistance, with the "training load" increasing exponentially as the trainees approached the extended knee joint position 
• doing lungs with elastic resistance resulted in higher levels of erector spinae and gluteus activity and was more posterior kinetic chain-dominant, which means that they were characterized by higher levels of hamstring, gluteus and erector spinae activity 

The reasons for these differences are actually of biomechanical nature and the outcomes will probably change, if you used the bands differently. So, yes, wrapping the bands around your back / posterior shoulders will be necessary; and yes, only if you use bands similar to the close loop elastic 41 inch bands  (Iron Woody, MT, USA) the scientists used in the study will allow for identical effects (this obviously doesn't mean that you cannot do it with whatever other band you have grabbing them with your hands, but specifically the posterior kinetic chan-dominance is probably not going to be that pronounced if you do that. Why? Because you will miss the anterior pull from the distal attachment of the band below the leading foot, from where it runs to the contralateral shoulder - a pull of which Jakobsen and his colleagues argue that it ...

"[...] creates the need for generating a high net hip extensor moment. In result [...] gluteus, erector spinae and hamstring muscle activity seemed to be elevated in lunges using elastic resistance indicating an effective targeting of the hip and spinal extensor muscles throughout the range of motion." (Jakobsen. 2012)

Done the "right" way, lunges with appropriately selected elastic exercise bands (not the ones you get bundled with Kellog's Special K, or whatever ;-) can therefore be a very effective tool for thigh, hip and back development, and can - with more flexible bands - used as "an ideal exercise modality for the rehabilitation and prophylactic prevention of musculoskeletal disorders" (Jakobson. 2012).

10 scientific pieces of evidence to built a case for explosive training

If the Jakobsen study ain't enough to convince you to spend at least a couple of minutes thinking about whether or not explosive training or plyometrics (which is basically explosive training with body weight exercises) could make a valuable adjunct to your current training regimen the following 10 studies may put you in the right way:

• How can you easily implement explosive training into your current routine? There are obviously a million of ways you can implement plyometrics and explosive exercises, but if you simply wanted to incorporate them on a strength training day, as an additional, different training stimulus, the protocol the researchers in the PGC-1 α-4 study (see The IGF-1 up- & myostatin down - regulator) looks actually as if it was worth copying. This would mean that you start out with a ballistic movement (B), head into a strength part (S) and then finish up with a hypertrophy exercise (H).
  
  For leg day this could look like this: (B) 3 sets of ballistic lunges - 10-12 reps, use 66% of 10RM; (S) 5 sets of 5 reps on the leg press or in the squat rack (I suggest the leg press because it's less injury prone with really high weights), stop 1 rep away from failure; (H) 4 sets of 10 reps of deep barbell squats a 10RM + regular calf training.
  
  Obviously, this is just one way and not the way: You can also do a plyometrics only circle training or do a couple of sets of plyos + a LISS session on a separate day, etc.
  
  Be creative! Test your ideas and see how you feel, but don't simply add them on top of an already overcrowded workout!
  You can safely combine classic resistance training with explosive lifting without hampering the performance in one or another (Brandenburg. 2005)
• The addition of explosive training and high-resistance interval training to the programs of already well-trained cyclists improve exercise efficiency and anaerobic threshold and thus produce major gains in sprint and endurance performance (Paton. 2005)
• If you want to improve your 1-RM max, doing a low volume (2 reps) set of explosive push ups, or  2 medicine-ball (3 to 5 kg) chest passes 30s before the actual lift can help (Wilcox. 2006)
• Complex training, i.e. combination of heavy lifting and explosives yields higher performance gains than heavy lifting and plyometrics, alone, across all age groups (20, 40, 60y; cf. Dodd. 2007)
• Explosive resistance training is safe and well tolerated in healthy women even in the eighth decade of life and elicits adaptive neuromuscular changes in selected physiological variables that are commonly associated with the risk of falls and disability in aged individuals (Caserotti. 2008)
• Explosive plyometrics sessions comprising maximal unilateral countermovement jumps (CMJs), calf and squat plyometric jumps, and short sprints are as effective as shuttle runs in improving maximal running speed in young elite soccer players (Buchheit. 2010)
• Pimping a regular soccer training with two plyometrics session per week makes it more effective in building general athletic performance (Chelly. 2010)
• Plyometrics are safe for young children (5-14y) and beginning at 50-60 jumps a session and increasing exercise load weekly results in the largest changes in running and jumping performance (Johnson. 2011)
• Explosive isometric contractions induce neural and mechanical adaptations leading to large increases in maximum voluntary force production esp. during the early phase of a movement (50ms, +54%; cf. Tillin. 2012)
• When adjusted to absolute force production, the evoked capacity of the knee extensors for explosive force production and the ability to utilize that capacity during explosive voluntary contractions is similar for males and females (Hannah. 2012)

Bottom line: I guess with the concluding review that obviously raises no claim to completeness it should be clear that the complementation of, yet not (necessarily) the replacement of classic strength & hypertrophy training with plyometrics or explosive lifting with relatively low weight constitutes an effective means to increase the neuronal activation and thus exponentiate subsequent strength and muscle gains.

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.

You should be aware, though that despite the fact that plyometrics and light load explosive lifting do not put a similar strain on your body as the standard high intensity high volume BB routines and will thus probably require less time to recuperate, their incorporation into your routine will make it necessary to cut back on the overall volume of the rest of the exercises (I assume you will up your reps on the plyos anyway, so the total time under tension wouldn't be an issue). Whether you decide to replace a HIIT or regular cardio workout with a longer full body plyometric workout, or doing one exercise less during a hypertrophy specific strength workout in order to make room for additional plyometrics (see example workout to learn how that could look like) is up to you and depends on your current goals and training status.


References:

• Buchheit M, Mendez-Villanueva A, Delhomel G, Brughelli M, Ahmaidi S. Improving repeated sprint ability in young elite soccer players: repeated shuttle sprints vs. explosive strength training. J Strength Cond Res. 2010 Oct;24(10):2715-22.
• Brandenburg JP. The acute effects of prior dynamic resistance exercise using different loads on subsequent upper-body explosive performance in resistance-trained men. J Strength Cond Res. 2005 May;19(2):427-32.
• Caserotti P, Aagaard P, Larsen JB, Puggaard L. Explosive heavy-resistance training in old and very old adults: changes in rapid muscle force, strength and power. Scand J Med Sci Sports. 2008 Dec;18(6):773-82.
• Chelly MS, Ghenem MA, Abid K, Hermassi S, Tabka Z, Shephard RJ. Effects of in-season short-term plyometric training program on leg power, jump- and sprint performance of soccer players. J Strength Cond Res. 2010 Oct;24(10):2670-6. 
• Desmedt JE, Godaux E. Ballistic contractions in man: Desmedt JE, Godaux E. Ballistic contractions in man: characteristic recruitment pattern of single motor units of the tibialis anterior muscle. J Physiol. 1977 Jan;264(3):673-93.
• Dodd DJ, Alvar BA. Analysis of acute explosive training modalities to improve lower-body power in baseball players. J Strength Cond Res. 2007 Nov;21(4):1177-82. 
• Frost DM, Cronin JB, Newton RU. A comparison of the kinematics, kinetics and muscle activity between pneumatic and free weight resistance. Eur J Appl Physiol. 2008 Dec;104(6):937-56.
• Hannah R, Minshull C, Buckthorpe MW, Folland JP. Explosive neuromuscular performance of males versus females. Exp Physiol. 2012 May;97(5):618-29. 
• Jakobsen MD, Sundstrup E, Andersen CH, Aagaard P, Andersen LL. Muscle activity during leg strengthening exercise using free weights and elastic resistance: Effects of ballistic vs controlled contractions. Hum Mov Sci. 2012 Dec 8.
• Johnson BA, Salzberg CL, Stevenson DA. A systematic review: plyometric training programs for young children. J Strength Cond Res. 2011 Sep;25(9):2623-33.
• Paton CD, Hopkins WG. Combining explosive and high-resistance training improves performance in competitive cyclists. J Strength Cond Res. 2005 Nov;19(4):826-30. 
• Sakamoto A, Sinclair PJ. Muscle activations under varying lifting speeds and intensities during bench press. Eur J Appl Physiol. 2012 Mar;112(3):1015-25.
• Tillin NA, Pain MT, Folland JP. Short-term training for explosive strength causes neural and mechanical adaptations. Exp Physiol. 2012 May;97(5):630-41.
• Wilcox J, Larson R, Brochu KM, Faigenbaum AD. Acute explosive-force movements enhance bench-press performance in athletic men. Int J Sports Physiol Perform. 2006 Sep;1(3):261-9.

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.

SuppVersity EMG Series - Gluteus maximus, Quadriceps femoris, Gastrocnemius, Soleus & More: The Very Best Exercises for Tree-Trunk Legs and Herculean Calves

Actually, it would make as much sense to split this part of the SuppVersity EMG Series in two, if not three individual analyses, as it would to split your leg workout over two if not three days. In practice, however, most trainees go through the grueling torture of the dreaded "leg day", just once a week and thus I will mirror this practice by writing a similarly gruelingly long blogpost on the best exercises for the major

Image 1: The major muscle groups
of your legs. Quadriceps, adductors,
abductors, gluteus, hamstrings,
gastrocnemius & soleus



• the quadriceps (red) - powerful extensors of the knee joint;crucial in walking, running, jumping and squatting; strongest and leanest muscle in the human body
• the gluteus (yellow) - three muscles that make up the buttocks: the gluteus maximus muscle, gluteus medius muscle and gluteus minimus muscle;
• the hamstrings (blue) - comprises the semitendinosus, semimembranosus and the short and long head of the biceps femoris, of which the former extend the hip when the trunk is fixed, flex the knee and medially (inwardly) rotate the lower leg, when the knee is bent, while the latter extend the hip (e.g when we begin to walk), flex the knee and laterally (outwardly) rotate the lower leg when the knee is bent

as well as the "minor" muscle groups of your legs

• the adductors (cyan) & abductors (magenta) at the inside and outside of the tighs, and
• the gastromenicus (light green) & soleus (highlighter green), the major muscles of your calves

In the end it is the the muscular development of all of them that eventually distinguishes the men from the boys. And by the way, playing football or, here in Germany, soccer, is no excuse for not training your legs!

Chest	Biceps	Back	Core	Legs	Triceps	Shoulders
Navigate the SuppVersity EMG Series - Click on the desired body part to see the optimal exercises.

In view of the sheer amount of information this part of the EMG Series is going to contain, I will, without further elaborations, go right into an analysis of the most effective exercises, as measured by electromyography (10 male resistance-trained subjects, mean age 22y, mean body-fat 13%; data from Boeckh-Behrens & Buskies. 2000) for all the major and supposedly minor muscle groups of your legs. I. The best exercises for the four heads of the quadriceps Those of you who have read any of the previous parts of this series will already be familiar with the idea of "isolation" being more of a shift in which part of a muscle takes the greatest hit and not so much about training a single strain of a complex muscle such as the quadriceps with its (who would have guessed) four heads. If I am talking about "best exercises for the inner, outer or whatever part" of any given muscle - and this goes for the whole EMG series - what is meant by that is a relative increase in intensity in a given part of a muscle over the rest. Always keep that in mind.

Image 2: Turns out the hack squat is the
most effective exercise. In that, going deep
(50° knee angle) is only slightly more taxing
on the quads than the standard
and much safer 90° knee angle.

The most effective exercises with standard equipment:

1. Hack squats, lying on machine, 50° knee angle
2. Hack squats, lying on machine, 90° knee angle
3. Squats, barbell, 70° knee angle
4. 45° leg press, 90° knee angle
5. Squats, barbell, 90° knee angle
6. Squats, barbell, 40° knee angle

If you take a look at the results in detail (figure 1), you will notice that the differences between the most (hack squats down to a knee angle of 50°) and the least effective exercise (leg extensions) are far from being earth-shattering.

Figure 1: Relative EMG activity of all four heads of the quadriceps during hack squat, leg press, squat and leg extension variations in comparison to barbell squatting to parallel (knee angle 75°); data adapted from Boeckh-Behrens & Buskies. 2000

What I consider of particular importance is that both in the case of the hack- as well as in the case of the "standard" barbell squat, going beyond parallel (knee angle <70°) is not worth the increased risk of injury (cf. figure 2).

Figure 2: Shear and compressive forces during squat exercise measured at different knee angles; expressed as percentage of the sum of body weight + load (data adapted from a compilation in Escamilla. 2000)

While the EMG activity of the quads may be marginally improved in the case of the hack squat (+0.38%), doing one's squats "ass to the ground", as some people like to call it, actually reduces the quad activity by -10.34%.

Image 3: 45° leg press with a hip angle of 85°; the
smaller hip angle (compared to the hack squat)
translates into  a -16% lower activity of the
quadriceps femoris (image everkinetic.com)

Did you know that the smaller the angle of your hip joint (this is in most cases equivalent to the more upright you are sitting or lying on a machine), the smaller is the EMG activity of the quadriceps femoris. During the hack squat exercise, for example the angle of your hip joint is ~100°, the 45° leg press facilitates an angle of ~85° and on the seated leg press the angle is only ~50°. While this does not lead to an 1:1 reduction in EMG activity, the latter is in fact, -16% and -22,5% smaller for the 85° and 50° hip joint angles on the respective exercises.

Training the inner and outer part of the quads Now, if you are a bodybuilder, you will probably be trying to build those "teardrops" (for all real experts who have no clue what those gym-bros refer to as "teardrops", this is the m. vastus medialis, cf. image 3), which actually does not so much look like a tear drop, as it sometimes takes shedding a few tears to get it growing. With respect to the m. vastus medialis Boeckh-Behrens and Buskies have to say that

[the inner part of the quadriceps] is maximally activated via variants of the horizontal leg presses / hack squats - either deep [knee angle <70°] with less weight or not deep [knee angle >70°] with more weight - variations in weight and knee angle tend to be equivalent.

So after all, even your "tear drops" benefits most if you just keep doing those exercises that hammer the quads, i.e. all four heads, as a whole. A slightly narrower stance, however, may be advantageous, while the positioning of the feet, i.e. parallel or with your feet pointing outward at a 30° angle seems to be negligible (+/- 0.25%).

Figure 3: Relative EMG activity of the outer part of the quadriceps (m. vastus lateralis) during barbell squat and single legged squat variations in comparison to barbell squatting to 90° knee angle; data adapted from Boeckh-Behrens & Buskies. 2000

Image 4: Inner (vastus medialis),
medial (vastus intermedius
& rectus femoris) and outer
(vastus lateralis) parts of
the "quads"

As you can see in figure 3, things are quite different, when it comes to the outer part of the "quads". Whereas the standard squat with high loads provides maximal muscle stimulation of the m. vastus lateralis, even if you do not even go down parallel to the floor (knee angle 70°), doing the "full squat" down to 40° with an appropriately lighter weight takes away -18% of the stimulus. Similar results can be seen for the isolation exercise single legged squats, where likewise the principle for maximal muscle stimulation reads more weight, greater knee angles (not going past parallel) - a principle, which can also help you keep injury free, as long as you do not wrench it as long as it say more weight and a smaller knee angle, in which case it is a safe bet that you would hurt yourself - probably sooner, than later. Training the medial part of the quads In view of what has been said before with regards to the maximal activation of the fashionable "teardrop" muscle, it is not really surprising that the usual suspects, i.e. the hack squat and the leg press are among the most effective exercises for the medial part of the quads, i.e. the m. vastus intermedius and the  m. rectus femoris, as well.

Figure 4: Relative EMG activity of the medial part of the quadriceps (vastus intermedius & rectus femoris) during selected exercises in comparison to hack squats to a 50° knee angle; data adapted from Boeckh-Behrens & Buskies. 2000

Figure 4 does yet go to show you that there is one relatively unknown "special exercise" for soccer players, as Boeckh-Behrens and Buskies like to call it, that outperforms even the hack squat. It's basically the leg kick you see the ladies do with those straps attached to their ankles in order to build one of those J'Lo-ish behinds, but in this case you do it the other way around, or, as the authors suggest, "think of kicking a ball". The +19% higher EMG activity compared to the hack squat (similar results have been found for the standard leg extensions vs. squats by scientists from the Marquette University in Milwaukee, Wisconsin; Ebben, 2009), suddenly makes, what you probably regarded as one of those ridicolously girly exercises, look like a worthwile addition to your regimen... well, at least, in case you are one of those rare exceptions who have an underdeveloped rectus femoris ;-)

Speaking of girly exercises... while it certainly is manly to squat 500lbs, it is not advisable to do so on a daily base. Even the strongest men in the world regard their training sessions asexactly that, the "process of developing the bodily vigour and endurance by systematic diet and exercise, so as to fit for some athletic feat" (Oxford English Dictionary, "training"), or, in other words, as the means to an end. Remember: King-size egos rarely built king-size quads.

II. The Best Exercises for The Gluteus maximus
 

Image 5: Atlantic Fitness' interpretation
of what Boeckh-Behrens & Buskies
call a "hip pendulum"

If you have already taken a look at the data in figure 5, you are probably now asking yourself what this strange leg curl variety that is supposed to activate the glutes ~2.3x as effective as a deadlift is all about. Those of you who read the core-episode of this series and the information about the best exercises for the erector spinae, in particular, will be familiar with its name, however. In essence, this is a standard leg curl, but instead of pushing your ties into the pad you are lying on, you try to lift them up, i.e. to curl your hips back, and forcefully contract the muscles of your lower back, your gluteus maximus and your hamstrings. If that's too complicated for you or just doesn't feel right, you can still look out for what Boeckh-Behrens & Buskies call a "hip pendulum" (cf. image 5) and use that instead.

Figure 5: Relative EMG activity of the m. gluteus maximus during selected exercises in comparison to deadlifts using a weight that matches your own body weight; data adapted from Boeckh-Behrens & Buskies. 2000

Of the exercises without additional weight, only leg kick variations, particularly if they are done with peak contractions and/or ankle weights, provide appreciable muscle stimuli, the intensity of which is about equal to to the leg kicks on the hip pendulum (cf. figure 4). III. The Best Exercises for the Hamstrings For the hamstrings the good old lying leg curls are what biceps curl are for the two-headed muscle of your upper arm. And, in fact, the results of the EMG measurements by Boeckh-Behrens & Buskies confirm that generations of trainees cannot be wrong. Similar to the concentration curls in the case of the biceps, only the use of intensity techniques, i.e. partials in the stretch position or peak contractions elevates the already phenomenal EMG values of the standard variety of the lying leg curls to 134% and 112% of the activity measured on the reference exercise (cf. figure 5)

Figure 6: Relative EMG activity of the muscles of the hamstrings during selected exercises in comparison to standard lying leg cursl; data adapted from Boeckh-Behrens & Buskies. 2000

Done correctly, i.e. with a leg angle of 100°, the leg or hip lift is the only body-weight exercise that can compete. With <50% of the muscle activity of the standard lying leg curls, hyperextensions, on the other hand, will do little for your hamstring development.

Did you know that doing partials and peak contractions is particularly effective eccentric exercises? On concentric exercises such as the squat, on the other hand, they increase your chance of getting injured and contribute little to the efficiacy of your training. Tip: If you are talking to your gym partner or, god-behold, your clients about these intensity techniques, you better not call them "X-reps "- otherwise you could be charged by some clever business men who know how to relable training techniques that have been around ever since the early days of physical culture in order to monetize on these "revolutionary new training techniques".

Image 6: An adductor machine,
as you probably know it from
your gym, as well.

IV. The Best Exercises for Adductors and Abductors

As you probably have expected, the adductor and abductor machines that are mostly operated by the female gym members, are the reference exercises to train the muscles on the inner and outer sides of your tighs. Unfortunately the build of these machines varies from one manufacturer to another, so that you can hardly be sure whether or not your adductor machine will produce the same muscular activation as the ones used in the study. The same holds true for the funky hip pendulum machine, the use of which as an adductor or abductor trainer is pretty tricky, anyways.

Figure 7: Relative EMG activity of the adductors and abductors during selected exercises in comparison to the respective machines (since the exact value for the abductor machine was not given by the authors, the latter is an estimation based on the rank of the exercise); data adapted from Boeckh-Behrens & Buskies. 2000

Viable alternatives for these machine based exercises are the cable adduction (moving leg pulled in before the stabilizing leg) and, probably  to the surprise of those among you who refrain from doing body weight exercises completely, the side bridge with hip abduction. When you are squatting, on the other hand, only the adductors are significantly involved in stabilizing the movement. To further increase their activity, you can do your hack squats with a wider stance and your toes facing slightly outward (30°), which will increase the load on your adductors and intensify the exercise by +3%. V. The Best Exercises for the Calves While chicken legs are no exception especially in many of the fitness oriented gyms, toothpick calves are becoming more and more the rule, especially among those trainees who love to do their endless cardio sessions on an elliptical. At the same time few people want to spend an adequate amount of time in training their calves. It is thus all the more important to know which exercises are effective and which are not.

Figure 8: Relative EMG activity of the calf muscles during selected exercises in comparison to the standing calf raises; data adapted from Boeckh-Behrens & Buskies. 2000

As you can see, you cannot avoid doing any variety of calf raises unless you are satisfied with a >65% reduction in muscle activity of the calves when you are doing your lying leg curls for your hamstrings. That being said, there are a few tweaks that make the exercises even more effective. The first, thing you can always incorporate are peak contractions and forced contractions in the stretched position. Moreover, it is imperative that you do not actively bend the knees during the seated calf raise (no bouncing!), if you do not want to reduce the muscle activity by -11%. And in a similar vein, you also do not want to mess with foot position, because (surprisingly?) the parallel foot position is the one that activates the inner, as well as the outer part of the m. gastrocnemius maximally (cf. figure 8)!

Figure 9: Relative EMG activity of the m. gastrocnemius with different foot positions; data adapted from Boeckh-Behrens & Buskies. 2000

In that, it is worth mentioning that the overall activation of the calves is maximized during standing and bent-over (donkey) calf raises, while the m. soleus activity is highest when you do seated calf raises.

A rule of thumb with regards to the activation of m. gastrocnemius vs. m. soleus is "maximize knee angle (as in standing calf raises or donkey calf raises) to maximize gastrocnemius, minimize knee angle (as in seated calf raises) to maximize soleus activity". Note: It is nonetheless imperative (especially if you are using higher loads) not to forcefully lockout your knees, in order to avoid injury.

Image 7: "Real men" ain't ashamed of doing
donkey calf-raises like Dave Draper and
Arnold used to do it ;o)

Last but not least, a short note on the "high reps for calves"-myth. While I do not question that many trainees just don't feel their calves working, if they do not go into the 50+ rep range, this is not due to the anatomy, the fiber type or whatever crazy anomaly of the calf muscle, but simply due to a faulty execution of the respective exercises. Bouncing, not utilizing the full range of motion and insufficient time under tension (1 sec up, 1-2 sec hold, 3 sec down, would be an appropriate way to go), the by far commonest mistake I see in the gym is turning your calf into a toe exercise by not pushing from the balls of your feet, but from the toes. Now guess what, it takes some time until your toes are finally fatigued and your calves get some work to do ... what would you say, maybe 20-30 reps? Hmm... that would mean that of your 50 reps of calf raises 30 are toe raises and the last 20 actually train your calves - does not sound particularly effective, does it? V. Conclusion: Too Much Work for a Single Day! Now, that you have arrived at the end of this concise and yet super-long write-up on leg training, you should actually ask yourself how and why you have hitherto packed all that stuff into a single workout. Well, I guess, after all, this is a very reasonable question. Nevertheless, fitness competitors and body builders alike have demonstrated time and again that a single "leg day" per week can suffice to build spectacular legs. Is this all genetics or are those guys (and, of course girls) spending the whole day in the gym?

Video 1: Arnold leg training compilation;
only the strong will survive ;-)

Did you know that Arnold Schwarzenegger, as a teenager took a barbell into the woods, where he and his friends squatted till they couldn't stand. This does not go to say that this would be the way to go for anyone - especially not the drug free weekend warrior who just wants to keep in shape, but leg-day or not, whenever you train your legs you should take a look at your toothsticks and ask yourself "How many sets have I done for chest, biceps and triceps this week?" If you did more for those than your did for your legs, you better add another set of squats.

Well, I guess some of the "pros" actually spend the whole day in the gym, but a lot of dedication aside, most of them also use an array of "special equipment" to make those workouts extra productive. My personal experience, on the other hand, tells me that legs can in fact sustain much more volume than many trainees claim from themselves (cf. "Did you know...", above). Yet, while I would think that it was possible to do at least a single working set of all "optimal" exercises, the "EMG-optimized routine" I am going to suggest below deliberately shifts the focus from those "optimal" isolation exercises to the optimal varieties of those compound movements that have built such incredible powerful 38"+ tighs on which Tom Platz and some other old school bodybuilders were walking through the gym.

Did you know that compound exercises such as squats and deadlifts have been  found to increase the hormonal response to strength training? Well, I guess you did. What may however be news to you is that these temporary increments are hardly going to exhibit those steroid-like effects some trainees seem to be expecting. This does not mean that the value of these exercises is overrated (on the contrary!), but rather that the increase in GH or testosterone after an intense squatting workout is corollary to, not causative of the efficiacy of these exercises.

The reason for that is quite simple: While a set of barbell squats may not activate your glutes like the strange hip pendulum, your quads like the Beckham-ish leg kicks and your adductors like the girly adductor machine, it will nevertheless build adequate power and mass in all three of these muscles, fortify your core, your calves, your upper back and even help with conditioning and fat loss. In other word, as gruelling as they may seem compared to some of the machine based isolation stuff, compound exercises will still give you the most bang, in this case muscle and strength gains, for your bucks, i.e. the time you spent and the energy you invest in the gym.

Image 8: As long as you are injury free,
there is noo way to get around squatting
- one way or another (image everkinetic)

If you cannot do squats
use leg press machines
instead.

As a beginner always have a
qualified trainer show you how to squat.

An EMG-optimized routine There is of course a myriad of ways of combining the individual exercises, my personal recommendation for overall leg development (based on EMG measures) would yet be as follows*:

1. Squats - to parallel (70°), 6-10 reps
2. Hack squats - to 90°, 8-12 reps
3. Leg curls - peak contract. or partials, 10-12 reps Superset:
4. Donkey calf raise - peak contract., 12 reps
5. Seated calf raise - partials, 12 reps Optional
6. Adductor machine - 12-15 reps
7. Abductor machine - 12-15 reps

You may notice that I do not make volume (i.e. set) recommendations. This is due to the fact that I found that everyone has to find what works best for him / her in terms of optimal volume and training frequency. This may also change over time / according to lifestyle factors / nutrition and supplementation.

Want to Design a Killer Workout? Reduce the Rest Times and Burn 37% More Energy During Your Workout!

The squat may be a power exercise, but trust me, it will also help you to "look good naked"!

I guess it would be hilarious to call the simple insight that cutting the time you rest in-between sets during your squats can turn a regular into a killer workout would be news, right? Well, what about some figures to define "killer" as in one minute rest between sets vs. "regular" as in three minutes rest between sets squats, then? That's news, right; and we have to thank Nicholas A. Ratamess and his colleagues from the College of New Jersey for these insights.

I mean, huffing and puffing is one thing, but your subjectively perceived level of exhaustion and the very concrete, objectively measured data on the difference in energy expenditure and the contribution of aerobic (fat) and anaerobic (glucose) energy sources during a workout, as they are presented in the paper at hand, are two different animals.

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Apropos animal, you don't necessarily have to be a similar "animal" as the 22-year old subjects of the study at hand with their ~8-year training experience to perform the tightly controlled experimental workout, the researchers describe as follows:

"After BL [baseline] measures, each subject performed a warm-up consisting of 3 minutes of stationary cycling and 2–3 lightto-moderate sets (40–60% of 1RM) of the bench press and squat. Respiratory masks were temporarily removed from each subject during the warm-up to allow subjects to consume water one last time before initiating the protocols.

Find out how to optimally train your legs - The SuppVersity EMG Series - Gluteus, Quads & Co | read more

The protocols consisted of performing 5 sets of the bench press and 5 sets of the back squat for up to 10 repetitions using 75% of their predetermined 1RM. The BP group performed the bench press first, whereas the S group performed the back squat first. For all exercises, resistance remained constant while total numbers of repetitions were recorded. Heart rate and oxygen consumption data were collected during the entire protocol. In addition, a linear position transducer (Tendo Sports Machines, Trencin, Slovak Republic) was attached to the bar to measure power and velocity during each completed repetition."

On each of the three occasions the subjects reported to the lap, a different rest interval was used. With 1-, 2-, and 3-minutes of rest in-between sets, the and a standard 2-minute RI was used in between exercises, the study represents more or less what I see trainees do at the gym on a daily basis, as well... ok, the lazy "I just want to be strong"-10-minutes-of-rest-between-sets-fat-ass was not accordingly represented in the study at hand, but let's be honest, how many of the average trainees do actually fall into this category? I mean, if you ask people why they are going to the gym, they will either lie or tell you that they are there to "look better naked".

"Looking good naked" is a valid training goal, folks - so admit to it!

For most people sculpting their body may be only one of the reasons, but in the end, it usually comes down to this and "health" or "fitness", when you're getting honest answers from gym users.

Figure 2: The amount of energy the trainees expended on bench presses and squats was significantly higher with the 1-min rest periods (17% and 36%, for squats; 8% and 18% for bench presses; data based on Ratamess. 2014)

Against that background, the insight that short rest periods lead to significant increases in energy expenditure is highly relevant (Note: The energy expenditure was calculated by multiplying the total VO2 for the session x 5.05kcal/L). Losing fat is after all number one on the "looking good naked" priority list of most trainees and in spite of the fact that you won't lose any fat without dieting, the 36% higher energy expenditure of the 1min vs. 3min rest time workout could make the difference between ordinary and outstanding fat loss results... in spite of the increase in the respiratory exchange ratio, an indicator of an increased anaerobic contribution to the energy expenditure, by the way!

And what about building muscle? There is insufficient data to draw a firm conclusion, but based on the few hardly comparable studies we have suggest that shorter rest times in the 1-2 minute realm are also associated with a more pronounced growth stimulus (Willardson. 2006; de Salles. 2009) and have either no or a hardly significant, yet positive effect on muscle growth (Ahtianen. 2005; Willardson. 2008). Resting for more than 2 minutes between sets does therefore make sense only if you are training for strength.

Short rest times + 6 Simple Rules of Reasonable Weight Loss = Succes!

Unfortunately, the myth that "burning fat" during exercise was in any way relevant to your weight / fat loss success is as die hard as it is stupid and flawed.

Especially for the leaner folks out there, "burning fat" is absolutely irrelevant. In fact, the whole HIIT research appears to suggest that short intense, highly glycolytic exercise regimen are more suitable to shed body fat for athletic individuals than arduous multiple-hour workouts in the non-existing (!) "fat burning zone".

The reason I still recommend LISS as a preferable type of cardio training for the advanced trainee with three to four resistance training sessions per week is that all the "high intensity stuff" (don't neglect your strength workouts!) is going to overtax the sympathetic nervous system. The classic light-intensity steady state (LISS) work, on the other hand, offers a welcome parasympathetic stimulus to balance all the intense explosive training you're doing at the gym.

Never train to burn fat! I know this article could create the impression that it would be worth going to the gym to "burn fat", but in the end, the main determinant of fat loss is your diet. If the latter ain't in check, all the training is not going to help. So, you better think of your workouts as the tool to control the fat / muscle loss ratio on a diet.

Bottom line: If "looking good naked" is your goal and "losing fat" among your top priorities, the results of the study at hand clearly support the longstanding wisdom that cutting back on your rest times will give you the edge.

You got to be careful, though, without cutting back on your energy intake and following the 6-simple rules of reasonable weight loss, you are not going to be very successful. No matter, if you rest for 1, 2, 3 or 20 minutes - diet and exercise, exercise and diet: If you want to look good naked, the two are simply the front and back of a single coin - you cannot separate them.

References:

• Ahtianen, Juha P., et al. "Short vs. long rest period between the sets in hypertrophic resistance training: influence on muscle strength, size, and hormonal adaptations in trained men." The Journal of Strength & Conditioning Research 19.3 (2005): 572-582.
• de Salles, Belmiro Freitas, et al. "Rest interval between sets in strength training." Sports Medicine 39.9 (2009): 765-777.
• Ratamess, Nicolas A., et al. "Acute Oxygen Uptake and Resistance Exercise Performance Using Different Rest Interval Lengths: The Influence of Maximal Aerobic Capacity and Exercise Sequence." Journal of Strength & Conditioning Research 28.7 (2014):1875–1888.
• Willardson, Jeffrey M. "A brief review: factors affecting the length of the rest interval between resistance exercise sets." The Journal of Strength & Conditioning Research 20.4 (2006): 978-984. 
• Willardson, Jeffrey M., and Lee N. Burkett. "The effect of different rest intervals between sets on volume components and strength gains." The Journal of Strength & Conditioning Research 22.1 (2008): 146-152.