# High Reps vs. Heavy Weights: Which is Better for Muscle Growth?



## Arnold (Jun 1, 2009)

*High Reps vs. Heavy Weights: Which is Better for Muscle Growth?* 
by Robbie Durand   

_???Everyone wants to be a bodybuilder, but no-one wants to lift heavy ass weights!???_
-Ronnie Coleman

    Muscle growth is a complex process; professional bodybuilders are divided into two camps: the light weight, high rep camp and the heavy weight.  In order for a muscle to grow, muscle overload must occur with resistance exercise - no argument there, however several Books have advocating high rep exercises to stimulate muscle growth.  The best example, the 50 rep squats to blast leg muscle to grow is a commonly method to blast leg muscles into growth. The most famous bodybuilder advocating high reps for muscle growth was Tom Platz; he was famous for sets with reps of 20 to 30 in the squat. A small reminder, Platz was known to squat 500 pounds for over 30 reps!!!  Proponents of the high rep training claim that high reps increase blood flow which enhance nutrient delivery, cause massive increases in Nitric Oxide and greater muscle pumps which stimulate muscle growth.   


*Vascular Occlusion with Light Weight Produces Muscle Hypertrophy*

It was previously thought that only performing resistance exercise at a load greater than 65% was enough to stimulate muscle growth.  However, some recent studies have reported that muscle tension is not the only way to produce muscular hypertrophy. For instance, a low-intensity (~50% 1RM) resistance training performed with leg extensions caused a marked increase in muscular size [~12% gain in muscle size and strength (~20% gain) when combined with moderate vascular occlusion8. The effects of these exercise training regimens with restricted muscular blood flow are likely mediated by the following processes: 1) stimulated secretion of growth hormone by intramuscular accumulation of metabolic byproducts, such as lactic acid10; 2) moderate production of free radicals and tissue damage promoting tissue growth9; and 3) additional recruitment of fast-twitch fibers in a hypoxic (low oxygen) condition11. These studies suggest that the muscle mass building effects of resistance exercise involves not only muscle tension (weight) but also metabolic, hormonal, and neuronal factors.  Higher repetition exercises has been shown to increase testosterone, growth hormone (GH) and insulin-like growth factor 1 (IGF-1)1,2,3,4.   You will definitely feel a greater muscle burn with a lighter weight and feel more pumped, but does a light weight high rep program such as the 50 rep squat routine lead to greater muscle growth?


*Light Weight Exercise vs. Heavy Weights: Which is Better?*

    Researchers tested a light weight protocol and a heavy resistance exercise program to determine if light weight programs with lots of reps can stimulate muscle growth.  Researchers took 12 healthy young men and made them perform 12 weeks of resistance exercise on a leg extension machine; they performed three workout sessions per week.  They performed a total of ten sets were assigned to two groups:

A.)    One leg with light weight -36 repetitions per set (15% of a 1-RM)
B.)    The other leg with heavy weight- 8 repetitions per set (70% of a 1-RM)

Here is what really interesting, even they performed different rep ranges, and both groups performed the same workout volume.  The good thing about this study is that the subject???s served as the own control???s so they were not being compared to other people.  


*Heavy Resistance Exercise Beats Light Weight-High Rep for Muscle Size*

    At the end of 12 weeks, the cross sectional size or muscle growth of the each leg demonstrated increases in muscle size but the heavy resistance group demonstrated greater gains in muscle mass5. The heavy resistance exercise group demonstrated a 7.6 ± 1.4% gain in muscle mass while the light weight group gained 2.6 ± 0.8%.  The heavy resistance training group also gained greater increases in muscle strength as well.   The study shows that light weight/high rep routines do increase muscle mass but just not to the same extent as heavy resistance exercise.  Despite getting a good muscle pump, you are not going to grow like loading up the bar with some iron!  When I read this study, I remember an episode of NO BULL RADIO where Dave and John were discussing; ???Who was the strongest builder ever????  Several names were mentioned: Johnnie Jackson, Dorian Yates, and Greg Kovacs.  Flex Wheeler set the recode straight, ???Ronnie Coleman was the strongest bodybuilder ever...Period!???  Is it any coincidence that as heavy as Ronnie trained, he also racked him up eight Mr. Olympia???s!  No high rep training for Ronnie, only heavy weights!!


*Muscle Hypertrophy without Increases in Acute Anabolic Hormones*

Another interesting finding was that the study found increases in muscle hypertrophy that occurred without increases in circulating anabolic hormones.  This finding of increases in muscle growth without changes in circulating levels of anabolic makes one question: How important are the acute anabolic hormone responses to exercise?  When I first started studying exercise endocrinology, I thought that the workouts that caused the greatest increase in anabolic hormones had to increase muscle mass.  Current research shows that acute anabolic hormones responses are important but are not the Holy Grail for increasing muscle size.  Remember, endurance exercise can produce considerable increase in GH and testosterone in response to exercise yet they don???t produce muscle hypertrophy.  Powerlifters demonstrate significant muscle size yet the typical powerlifting workout produces low anabolic hormone responses.  Previous studies have shown that ingestions of whey protein before exercise blunted testosterone and GH responses6 but many studies suggest that pre-exercise protein supplementation is essential for increasing muscle mass.  I would not miss a pre exercise whey protein shake in hopes of a better acute testosterone response. 


*Muscle Tension May be May Important than Acute Hormone Responses*

This research also is in conjunction with Researchers at the Exercise Metabolism Group at McMaster's University who recently reported that muscle hypertrophy took place without acute increases in anabolic hormone concentrations7.  Ten healthy young male subjects performed unilateral resistance training for 8 week (3 days/week). Unilateral resistance exercise is basically where you train one leg, while the other leg is used as a control or untrained muscle.  Exercises performed in the study were knee extension and leg press performed at 80-90% of the subject's single repetition maximum (1RM). Blood samples were collected before, immediately after, 30, 60, 90, and 120 minutes post-exercise. The first training bout and following the last training bout were analyzed for total testosterone, free-testosterone, GH, and insulin-like growth factor-1, along with other hormones. Thigh muscle cross sectional area of the (vastus lateralis) were measured pre- and post-training. Acutely, no changes in GH, testosterone, or IGF-1 concentrations were observed in the 90 min period following exercise and there was no influence of training on the anabolic hormones measured.  GH did show a moderate increase 30 minutes post-exercise but returned to baseline values by 90 minutes. Training-induced increases in muscle hypertrophy were observed in type IIb and IIa muscle fiber. No changes were observed in muscle size in the untrained leg. In conclusion, unilateral training induced local muscle hypertrophy only in the exercised limb, which occurred in the absence of testosterone, GH, or IGF-1 circulating levels.  The moral of the story, don???t get so caught up in the acute anabolic hormone response that you limit your poundage.

A light weight, high rep protocol does produce muscle hypertrophy, but light weight, however heavy resistance exercise produces greater muscle mass gains.   Muscle "burn" does not stimulate growth, overload stimulates growth. ???Muscle pumps??? and "feeling the burn" are not really what building muscle is about nor is it a good indicator of muscle growth as the study demonstrates. You can get a good "burn" by doing 20-30 repetitions; however, training at that rep range does not efficiently overload the muscle. The bottom line of the study is that training loads less than 70% of a 1-RM are not going to induce significant gains in muscle mass or strength.  High rep training may be good for muscle pumps but not good for increasing muscle size or strength.

*Key Points:*

- Light weight, high repetition workouts do not stimulate muscle growth effectively; heavy resistance exercise is a greater stimulator of muscle growth.

-  Muscle hypertrophy occurred despite increases in anabolic hormones; muscle growth factors (IGF-1, MGF) may be more important than the acute hormone increases.


References:
1.    Hakkinen, K., and Pakarinen, A. Acute hormonal responses to two different fatiguing heavy-resistance protocols in male athletes.   J. Appl. Physiol.  74: 882-887, 1993.
2.    Raastad, Truls., Bjoro, Trine., and Hallen, Jostein.  Hormonal responses to high- and moderate-intensity strength exercise.  Eur.  J. Appl. Physiol. 82:121-128, 2000.
3.    Kraemer, W.J., Marchitelli, L.J., Gordon, S.E., Harman, E., Dziados, J.E., Mello, R., Frykman, P., McCurry, D., and Fleck, S.J. Hormonal and growth factors responses to heavy-resistance exercise protocols.  J. Appl. Physiol. 69:1442-1450, 1990.   
4.    Hakkinen K, Pakarinen A. Acute hormonal responses to two different fatiguing heavy-resistance protocols in male athletes. J Appl Physiol. 1993 Feb;74(2):882-7.
5.    Holm L, Reitelseder S, Pedersen TG, Doessing S, Petersen SG, Flyvbjerg A, Andersen JL, Aagaard P, Kjaer M. Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity. J Appl Physiol. 2008
6.    Hulmi JJ, Volek JS, Selänne H, Mero AA. Protein ingestion prior to strength exercise affects blood hormones and metabolism. Med Sci Sports Exerc. 2005 Nov;37(11):1990-7.
7.    Wilkinson SB, Tarnopolsky MA, Grant EJ, Correia CE, Phillips SM. Hypertrophy with unilateral resistance exercise occurs without increases in endogenous anabolic hormone concentration. Eur J Appl Physiol. 2006 Dec;98(6):546-55.
8.    Takarada Y, Sato Y, and Ishii N. Effects of resistance exercise combined with vascular occlusion on muscle function in athletes. Eur J Appl Physiol 86: 308???314, 2002.
9.    Takarada Y, Takazawa H, and Ishii N. Applications of vascular occlusion diminish disuse atrophy of knee extensor muscles. Med Sci Sports Exerc 32: 2035???2039, 2000.
10.    Takarada Y, Nakamura Y, Aruga S, Onda T, Miyazaki S, and Ishii N. Rapid increase in plasma growth hormone after low-intensity resistance exercise with vascular occlusion. J Appl Physiol 88: 61???65, 2000.
11.    Takarada Y, Takazawa H, Sato Y, Takebayashi S, Tanaka Y, and Ishii N. Effects of resistance exercise combined with moderate vascular occlusion on muscular function in humans. J Appl Physiol 88: 2097???2106, 2000. 


source


----------



## Rookeek (Jun 1, 2009)

Great post!

 If there was a similar post about Split vs Total Body Training that would be even more awesome!


----------



## gtbmed (Jun 1, 2009)

To me it makes sense.  If you're trying to train your body to lift heavy weights, your body is going to want to grow to get bigger and stronger and be able to stabilize and lift more weight.

But I think this somewhat overcomplicates a simple thing.  The key is to continue to try and get stronger.  You usually don't get bigger without getting stronger, so if your lifts are progressing, you'll probably grow.


----------



## ygbodybuilder10 (Jun 3, 2009)

i would choose heavy low reps no more than 10 reps


----------



## nkira (Jun 3, 2009)

This concurs with what Built has been saying, Go HEAVY!!


----------



## jderksen (Jun 3, 2009)

Rookeek said:


> Great post!
> 
> If there was a similar post about Split vs Total Body Training that would be even more awesome!



TMUSCLE.com | Full Body vs. Split Training


----------



## OneWheyOrAnother (Jun 3, 2009)

nkira said:


> This concurs with what Built has been saying, Go HEAVY!!



Yep, Built! is the man (I mean woman )

But she has been saying this for a while now, and I don't even Google things much anymore, I just read her blogs and posts and good quality answers.

And just to brag a little more, I live just on the border of the city beside hers


----------



## nkira (Jun 3, 2009)

I agree, her blog is condensed version of all the info out there, something like handy pocket guide....



chronicelite said:


> Yep, Built! is the man (I mean woman )
> 
> But she has been saying this for a while now, and I don't even Google things much anymore, I just read her blogs and posts and good quality answers.
> 
> And just to brag a little more, I live just on the border of the city beside hers


----------



## readyformore (Jun 4, 2009)

GREAT POST i read all of it and LOVED it but i have a question.


wouldn't your muscles eventually  start getting used to the low reps and lower muscle gain? lets say you workout low reps (7-8 or so) for one month then high reps (about 15) the next month and keep switching off, would you gain more muscle that way?


----------



## Built (Jun 4, 2009)

I do like the heavy lifting, it's true. 

But there's room in my heart for ALL the rep ranges. For example, Baby Got Back, in my blog, references an article by Thibaudeau called "three ways to get big". The Ian King - type split is based on an undulating periodization scheme, with low, medium and high rep work throughout the week. 

In my disturbed little mind, I see this approach - of training low-rep, heavy compounds (stimulates the sarcomere) and higher rep ranges as well (stimulates the sarcoplasm) - you're basically alternating between building the real-estate and building the infrastructure - with development comes increased need for plumbing, electricity... yanno, like the 'burbs. 

The way I see it, developing a suburb is similar to developing the body. You need a blood supply to feed the muscle. With more muscle added on, there is increased demand for support. They both need to grow, or you don't grow. 

As an aside, that's why I'm such a fan of low rep work while cutting - on reduced resources, you aren't building anything and you certainly aren't investing in infrastructure - you need to invest what little you have in hanging onto the real estate you don't want to lose!


----------

