The following article was written by Scott Stevenson – The original article can be found here
When it comes to resistance exercise programming, basic principles of training like intensity (relative load), volume, progression (or progressive overload), and periodization are the letters of a strength and conditioning coach’s alphabet. However, most of these coaches are programming for a sport, and the outcomes are concrete, quantifiable, and performance based, especially when it comes to lifting sports like powerlifting or Olympic weightlifting. Training logs and meet performance tell a solid story.
Definitions of a “sport” aside, it seems to me that bodybuilders may not be as focused on fine-tuning training as other athletes in the iron game. Muscle size, as an outcome measure, is more difficult to track than a one-rep maximum, for instance. How you look is what matters most in bodybuilding, of course, but most bodybuilders will even tell you that the mirror can play tricks on the mind, especially when dieting down for a show.
As far as the science of tracking muscle growth goes, the muscle biopsy technique was first employed just shortly before Arnold Schwarzenegger’s heyday (1), and thus far, you can’t pick up a home biopsy kit at the local drugstore. Only in the past few years have I noticed bodybuilders taking advantage of now readily available technology such as DEXA (dual-emission x-ray absorptiometry) for quantifying muscle mass (2). In depth, scientific case studies of bodybuilders growing in the off-season or prepping for competition are very rare (3, 4) as well.
In short, directly applicable training studies of advanced bodybuilders simply aren’t rolling off the presses (unless you consider the hundreds of “university studies” published only in supplement advertisements “science”). At this point, I think it’s simply not a typical or routine part of the bodybuilding culture, such as eating frequently or getting a base tan before stepping on stage, to endure the expense of sophisticated body composition testing to evaluate off-season or pre-contest progress. Similarly, bodybuilders don’t regularly train in teams (although this is a growing trend in the other competitive physique categories) where they can exchange training information with both each other and coaches, who can then synthesize results and formulate training strategies.
The Missing Principle
My contention is that frequency of training is a highly overlooked training principle, and even nearly forgotten when it comes to building muscle. In my experience, bodybuilders are very focused on “the set”—finding the right rep range, adding negatives, doing forced reps, doing drop sets, and doing various forms of cluster sets (5) like rest-pause sets (6) or muscle rounds (7). Secondarily, we’re focused on the workout per se—total sets and exercises—and most bodybuilders would be considered high volume trainers (8) following a split routine that hits a muscle group one time per week (9). I understand entirely and trained this way myself for many years. This training approach is what you most often see, read, and hear as the preferred method of training for muscle growth and the approach that probably (my best guess here) has produced the most IFBB professionals. High volume, once a week body part split training works, no doubt, at least for many people. However, there’s more than one way to skin a cat, and those in the know might now be thinking about the routines of successful IFBB pros like Dave Henry and Ronnie Coleman, whose tried and true routine included training each muscle group twice per week (10).
Put the Science Aside for a Moment
If you wanted to get better at just about anything, would you practice it just once weekly? Consider most any sport. How typical is training one time per week? Naturally, the stress of weight training is a bit different than playing table tennis, baseball, or even football, so there are substantial programming differences to be accounted for. Max effort squatting five times per week might be a tad much, but Olympic weightlifters are renowned for very high frequency training (11). Heck, one could even wage the argument that our bodies should be able to withstand one to two hours of kick ass training a day, even if training the same muscle groups. On the other hand, as I’ve noted previously, lifting and lowering the same load again and again might not fall within the definition of a “natural” act.
Back to the Science
When it comes to deriving a resistance training frequency that optimizes muscle growth, what does modern exercise science point to? In other words, if we compare a workout that engages the molecular mechanisms of muscle growth to taking a drug (with a given duration of action), how often should we “dose” our training sessions to ensure that we’re perpetually growing? How long does the protein synthetic response to a training session last? Bodybuilders are renowned for eating frequently. Should the same logic be applied to training? Beyond the single session, do training studies suggest a dose-response relationship for training frequency as it affects muscle growth?
Keep Your Mojo Working: Protein Synthesis
Probably the most common approach to bringing up a weak muscle group that I’ve seen (and used) over the years has been to train it more frequently. Daily calf training isn’t considered ludicrous, and Doggcrapp Training (Dante Trudel’s popular and effective invention) prescribes training the entire body three times every nine days. Beginners often train with full body splits, but this is quite rare for more advanced trainees nowadays (9). Some of you reading have probably tried John McCallum’s “squats and milk” program, better known as Randall Strossen’s amended formulation “Super Squats” (12). I can’t recall anyone who tried these high frequency whole body routines and said that they weren’t both effective and absolutely brutal. The latter quality may explain why they aren’t more commonplace.
If the purpose of training is to stimulate growth (“you don’t grow in the gym”), high frequency training makes sense biologically. The resistance exercise-induced increase in muscle protein synthesis only lasts between approximately 24 and 48 hours (13-15), perhaps as long as 72 hours if you’re a newbie to training (16). On the other hand, this glorious enhancement of muscle metabolism is actually shortened (17) and/or dampened in overall magnitude after you’ve been training for a while (18, 19). This may be one reason why “newbies” gain muscle so well, but more advanced trainees feel they need more voluminous sessions to evoke a growth response. Being advanced may simply mean that you need to buck up and train harder and more frequently if you want to maintain ‘round the clock elevation of protein synthesis. The obvious trick to training more frequently, however, is to temper the volume of training per session.
Is There a Dose-Response for Training Frequency and Muscle Growth?
A multitude of studies have been done that examine strength and/or muscle gain and training volume (number of sets), but some meta-analyses on the topic have barely addressed the notion of training frequency (20-22). Other meta-analyses have found that training two to three times a week with four to eight sets per movement seems ideal for strength (23, 24). An excellent review by Wernborn (25) suggests that same relationship holds with regard to training frequency and muscle enlargement: two to three sessions per week are ideal when it comes to making muscle grow. Interestingly, in his review, the highest rates of muscle growth for the elbow flexors (26) and quads (27) came from training four times and twelve times per week (using blood flow occluded walk training), respectively. Although these studies were very short, they support the logic that regular dosing with a protein synthetic stimulus results in rapid increases in muscle size.
Comparison of one, two or three sessions per week in both beginners and advanced trainees tells us, once again, that twice or thrice per week can be up to twice as effective for gaining muscle mass as once weekly workouts. When total training volume is equated—a very important training parameter to control for—three weekly sessions are better than one (28) and twice daily training wins out over one daily session (29) for gaining both size and strength.
The picture painted here isn’t that training splits that directly target a muscle (group) only once per week don’t work. There are thousands of examples of large bodybuilders who got that way using that approach. However, just like taking an aspirin in the morning may not treat a headache in the evening, the anabolic effects of a Monday training session may only last half the week, so why not train more often to keep your muscle growin’ mojo workin’?
Dude, You’re Off Your Rocker…
You might be thinking that I’m a bit crazy here: “Scott, I can’t possibly train a muscle group—really train it—twice or three times per week and not end up in an overtraining hole lickety split.” For those who haven’t done a high frequency program like DC Training, Super Squats, or something even more outrageous like one of Leo Costa’s inventions (e.g. Big Beyond Belief (30) or Titan Training (7)), I can understand your concerns. However, keep the following in mind:
- Very low training loads (even 30 percent of a 1RM) if taken to failure (31–35) can create a powerful growth stimulus. As mentioned above, high rep squat training has a good reputation in this regard. Also, employing lower load training is a great way to balance the wear and tear that heavy loads can have on your joints.
Only three to four sets can create a significant protein synthetic response and ultimately growth (31, 36–38). You don’t have to volume train yourself into oblivion with multiple maximum effort sets to create a growth response. Again, the key to making high frequency training work is adjusting the number of sets for each muscle group in a workout. Practically speaking, this is also necessary to avoid marathon sessions in the gym.
- Sets that focus on metabolic stress, epitomized by blood flow restriction (i.e. occlusion or Kaatsu training) can generate impressive muscle growth with minimal muscle damage and soreness (27, 39, 40). Daily training sessions (six or seven days per week) for the same muscle group aren’t uncommon with this style of training (27, 41–43). If formally occluding blood flow isn’t your cup of tea, maintaining muscle tension above about 50–60 percent of maximal effort, especially if using slow rep tempos (44), will substantially limit blood flow (45–47). Anyone who has intentionally trained with a “continuous tension” style, avoiding muscle relaxation between reps (e.g. not pausing at the top of the range of motion of a preacher curl or locking the knees at the top of a squat), knows that this is a sure fire way to accumulate painful metabolites.
If you trust in the strategy that training a weak muscle group more frequently will foster growth, what is keeping you from applying this strategy to elicit muscle growth overall? If you haven’t trained with high frequencies in the past but have tried just about every training intensification technique and dietary supplement known to bodybuilders since the days of Eugen Sandow, you may have some exciting newfound muscle growth to look forward to.
Bergström J, Hultman E (1967) A study of exercise on glycogen metabolism during exercise in man. Scand J Clin Lab Invest 19:218–28.
Modlesky CM, et al (1996) Density of the fat-free mass and estimates of body composition in male weight trainers. Journal of applied physiology 80(6):2085–96.
Manore MM, et al (1993) Diet and exercise strategies of a world-class bodybuilder. Int J Sport Nutr 3(1):76–86.
Rossow LM, et al (2013) Natural bodybuilding competition preparation and recovery: a 12-month case study. Int J Sports Physiol Perform 8(5):582–92.
Haff GG, et al (2008) Cluster training: A novel method for introducing training program variation. Strength Cond J 30:67–76.
Trudel D (2010) Interview regarding DC Training. In: Stevenson SW (editor), Costa L (2000) Titan Training Manual. Optimum Training Systems. At: #
Kraemer WJ, et al (1987) Physiologic responses to heavy-resistance exercise with very short rest periods. Int J Sports Med 8:247–52.
Hackett DA, et al (2013) Training practices and ergogenic aids used by male bodybuilders. J Strength Cond Res 27(6):1609–17.
Okabe M (2005) Ronnie Coleman: The Unbelievable! Mocvideo Productions. Video, 82 minutes.
Kraemer WJ, Fleck SJ (2007) Optimizing strength training: Designing nonlinear periodization workouts. Champaign, IL: Human Kinetics, pg. ix.
Strossen RJ (1989) Super squats: How to gain 30 pounds of muscle in 6 weeks. Nevada City, Calif.: IronMind Enterprises, pg. 107.
Chesley A, et al (1992) Changes in human muscle protein synthesis after resistance exercise. J Appl Physiol 73:1383–88.
Phillips SM, et al (1997) Mixed muscle protein synthesis and breakdown after resistance exercise in humans. The American Journal of Physiology 273(1Pt1):E99–107.
Cuthbertson DJ, et al (2006) Anabolic signaling and protein synthesis in human skeletal muscle after dynamic shortening or lengthening exercise. Am J Physiol Endocrinol Metab 290(4):E731–8.
Miller BF, et al (2005) Coordinated collagen and muscle protein synthesis in human patella tendon and quadriceps muscle after exercise. J Physiol 567(Pt3):1021–33.
Tang JE, et al (2008) Resistance training alters the response of fed state mixed muscle protein synthesis in young men. Am J Physiol Regul Integr Comp Physiol 294(1):R172–8.
Hartman JW, et al (2006) Resistance training reduces whole-body protein turnover and improves net protein retention in untrained young males. Appl Physiol Nutr Metab 31(5):557–64.
Phillips SM, et al (1999) Resistance training reduces the acute exercise-induced increase in muscle protein turnover. Am J Physiol 276(1Pt1):E118–24.
Krieger JW (2010) Single vs. multiple sets of resistance exercise for muscle hypertrophy: a meta-analysis. J Strength Cond Res 24(4):1150–9.
Krieger JW (2009) Single versus multiple sets of resistance exercise: a meta-regression. J Strength Cond Res 23(6):1890–901.
Wolfe BL, et al (2004) Quantitative analysis of single- vs. multiple-set programs in resistance training. J Strength Cond Res 18(1):35–47.
Rhea MR, et al (2003) A meta-analysis to determine the dose response for strength development. Med Sci Sports Exerc 35(3):456–64.
Peterson MD, et al (2005) Applications of the dose-response for muscular strength development: a review of meta-analytic efficacy and reliability for designing training prescription. J Strength Cond Res 19(4):950–8.
Wernbom M, et al (2007) The influence of frequency, intensity, volume and mode of strength training on whole muscle cross-sectional area in humans. Sports Med 37(3):225–64.
Narici MV, Kayser B (1995) Hypertrophic response of human skeletal muscle to strength training in hypoxia and normoxia. Eur J Appl Physiol Occup Physiol 70(3):213–9.
Abe T, et al (2005) Skeletal muscle size and circulating IGF-1 are increased after two weeks of twice daily Kaatsu resistance training. Int J Kaatsu Training Res 1:6–12.
McLester JRJ, et al (2000) Comparison of 1 Day and 3 Days Per Week of Equal-Volume Resistance Training in Experienced Subjects. The Journal of Strength & Conditioning Research 14(3):273–81.
Hakkinen K, Kallinen M (1994) Distribution of strength training volume into one or two daily sessions and neuromuscular adaptations in female athletes. Electromyogr Clin Neurophysiol 34(2):117–24.
Costa L (1998) Big Beyond Belief. Optimum Training Systems.
Burd NA, et al (2010) Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. PloS one 5(8):e12033.
Henneman E (1957) Relation between size of neurons and their susceptibility to discharge. Science 126(3287):1345–7.
Henneman E, Olson CB (1965) Relations between structure and function in the design of skeletal muscles. J Neurophysiol 28:581–98.
Carpinelli RN (2008) The size principle and a critical analysis of the unsubstantiated heavier-is-better recommendation for resistance training. Journal of Exercise Science & Fitness 6(2):67–86.
Sandee J (2009) The correct interpretation of the size principle and it’s practical application to resistance training. Med Sport 13:203–9.
Burd NA, et al (2010) Resistance exercise volume affects myofibrillar protein synthesis and anabolic signalling molecule phosphorylation in young men. J Physiol 588(Pt16):3119–30.
Mitchell CJ, et al (2012) Resistance exercise load does not determine training-mediated hypertrophic gains in young men. Journal of applied physiology 113(1):71–7.
Staples AW, et al (2011) Carbohydrate does not augment exercise-induced protein accretion versus protein alone. Med Sci Sports Exerc 43(7):1154–61.
Takarada Y, et al (2005) Rapid increase in plasma growth hormone after low-intensity resistance exercise with vascular occlusion. J Appl Physiol (1985) 88(1):61–5.
Wilson JM, et al (2013) Practical Blood Flow Restriction Training Increases Acute Determinants of Hypertrophy Without Increasing Indices of Muscle Damage. The Journal of Strength & Conditioning Research 27(11):3068–75. 10.1519/JSC.0b013e31828a1ffa. http://journals.lww.com/nsca-jscr/Fulltext/2013/11000/Practical_Blood_Flow_Restriction_Training.20.aspx
Abe T, et al (2006) Muscle size and strength are increased following walk training with restricted venous blood flow from the leg muscle, Kaatsu-walk training. Journal of Applied Physiology 100(5):1460–66.
Yasuda T, et al (2010) Effects of low-intensity bench press training with restricted arm muscle blood flow on chest muscle hypertrophy: a pilot study. Clin Physiol Funct Imaging 30(5):338–43.
Yatsuda T, et al (2005) Muscle fiber cross sectional area is increased after twice daily KAATSU-resistance training Int J Kaatsu Training Res 1:65–70.
Tanimoto M, Ishii N (2006) Effects of low-intensity resistance exercise with slow movement and tonic force generation on muscular function in young men. J Appl Physiol (1985) 100(4):1150–7.
McCully KK, et al (1991) Muscle metabolism in older subjects using 31P magnetic resonance spectroscopy. Can J Physiol Pharmacol 69(5):576–80.
Sadamoto T, et al (1983) Skeletal muscle tension, flow, pressure, and EMG during sustained isometric contractions in humans. Eur J Appl Physiol Occup Physiol 51(3):395–408.
Lind AR, Williams CA (1979) The control of blood flow through human forearm muscles following brief isometric contractions. J Physiol 288:529–47.