Why do 8 12 reps

Periodization is a system of training that organizes your workout into distinct cycles. Because each cycle has specific objectives, the number of reps for each varies sharply. Phase 1 : Preparatory, consisting of extremely high volume 15 or more reps, three to five sets and low resistance. Phase 2 : Hypertrophy, or growth, consisting of high volume eight to 12 reps, three to five sets and moderate resistance 50 percent to 75 percent of one-rep max. Phase 3 : Strength, consisting of moderate volume five or six reps, three to five sets and heavy resistance 80 percent to 88 percent of one-rep max.

Phase 4 : Power, consisting of low volume two to four reps, three to five sets and very heavy resistance 90 percent to 95 percent of one-rep max. To build the explosive strength necessary for competition, athletes frequently use Phase 4, the power phase. Keep reading for a simple three-month periodization cycle that can be used by both gym novices and grizzled veterans.

Devote one month to each phase, gradually increasing resistance while decreasing the number of sets as the month progresses. After the completion of this three-month cycle, actively rest run, hike, play basketball, etc. In the interest of simplicity, we have not changed the exercises between cycles. Traditionally, however, the exercises do vary. Note how the number of repetitions changes per phase. This will maximize growth by engaging the greatest number of muscle-fiber types.

In the study, 10 trained men performed 3 sets of 10RM biceps curls and machine chest flyes. Each exercise was performed with a different rest period: 1, 2, and 4 minutes for recovery. The shorter rest periods 1 and 2 minutes hurt the number of reps the guys could bang out early on in the workout; it also lowered training volume over multiple sets for both exercises—so keep this in mind!

Longer rests may benefit you in the long run. For the rest of the moves, which are compound exercises , meaning they work more than one body part and muscle group, your target amount of rest will vary depending on your goal. Read this definitive guide , which can cater to the hypertrophy and strength phase above and more. For access to exclusive gear videos, celebrity interviews, and more, subscribe on YouTube!

Since the fast-twitch fibers are the ones that grow the biggest and strongest and the slow-twitch fibers need to stay small for maximal endurance, it has been assumed that to really build maximal muscle size, the weight must be heavy enough to recruit the fast-twitch muscle fibers.

Now back to that weight that you could complete 20 reps of curls with: Yes, when you do the first few reps you are only recruiting the slow-twitch muscle fibers.

But as the reps continue and those slow-twitch muscle fibers fatigue, the brain starts calling on more and more of the bigger fast-twitch fibers with each and every rep completed. If you take that rep set to absolute muscle failure—the point at which you can't complete another rep—you recruited the same amount of fast-twitch muscle fibers as you did when you used a weight that limited you to one rep.

This is the real key to how higher rep sets performed with lighter weight may be better for muscle growth than doing fewer reps with heavier weight: Training to muscle failure. While recruiting the maximum number of fast-twitch muscle fibers may be crucial for muscle growth, there appears to be other factors involved. After all, if muscle growth was only about recruiting fast-twitch muscle fibers, the best way to grow would be to always lift a weight that limits you to one rep.

Yet, as we all know, that's not the best way to grow muscle. In fact, that's not even the best way to increase muscle strength. This is due to the fact that metabolic stress is also important for both muscle growth and muscle strength. Metabolic stress is created within the muscle when byproducts accumulate from the biochemical pathways used in the muscle cells to produce the energy required to lift the weight.

These byproducts signal other chemicals in the muscle, such as insulin-like growth factor-I, to come in and induce muscle hypertrophy. The byproducts even signal other chemicals to be released from other areas of the body.

For example, growth-hormone levels increase as levels of the metabolic byproduct lactic acid rise. These may all be important for increasing the process of muscle protein synthesis, which is ultimately how muscles grow. The best way to maximize metabolic stress is to do more reps. Higher reps increase the amount of biochemical byproducts that are produced. So as long as you take that high-rep set to muscle failure, you'll recruit the same amount of fast-twitch muscle fibers as a heavier set for fewer reps.

But you also induce greater metabolic stress. While all of this sounds good in theory, there's also research that supports this contention. Training with lighter weights is starting to sound a little more compelling, isn't it?

The first work that grabbed the attention of strength scientists and well-read bodybuilders everywhere was a study the group published in the online science journal PLoS Public Library of Science ONE.

Trained men performed four sets of leg extensions using either a weight that limited them to reps per set or a weight that allowed them to complete about 25 reps per set. They took all sets to muscle failure except for one additional group that used the rep weight, but didn't go to full muscle failure. However, both the rep and rep sets taken to failure increased muscle protein synthesis far greater than the rep sets not taken to muscle failure.

A study by the same researchers looked at what happens to muscle-protein synthesis following heavy- or light-weight training when subjects consumed a protein shake 24 hours after the workout.

They performed four sets of leg extensions using either a weight that they could lift for about reps or a weight they could lift for about 25 reps. Those doing the rep sets took each set to muscle failure, while half of those doing the rep sets went to muscle failure on all sets, while the other half didn't.

The researchers reported in the Journal of Nutrition that drinking a protein shake 24 hours after training to failure using either the heavy weight reps per set or the light weight about 25 reps per set significantly boosted muscle-protein synthesis higher than when they drank the same protein shake at rest or after weight training, but not going to muscle failure.

One trend that you should notice right away in these two studies is that the most critical factor in increasing muscle-protein synthesis, both immediately after training and for the 24 hours that follow, is to take all sets to muscle failure. That's the only way to recruit all of the fast-twitch muscle fibers and instigate sufficient metabolic stress. This data finally shut up all those strength-training experts who say you shouldn't train to muscle failure, at least not on most sets.

They claim that it leads to over-training and can actually interfere with strength and muscle growth. Of course, the first thing you'll notice about most of these so-called experts is the fact that their upper arms barely measure 15 inches. If their lack of muscle mass doesn't tip you off, then that kind of nonsensical reasoning about muscle failure tells you right away that they don't understand the basics of muscle physiology and, more specifically, never learned about the size principle.

It also tells you that they haven't been paying attention to the newer research that has been conducted, such as these two studies. As far as over-training goes, you have no worries about that as long as you follow a solid nutrition and supplement plan like the ones you find on my site.

They did intense labor for the majority of the day and only rested at night when the day was over. Do you honestly think after sitting on your ass all day at your desk job or in school that training intensely for minutes is going to cause you to over train?!

Get real! This is just an excuse for those who don't want to put in the hard work it takes to build real muscle. They'll blame their genetics when really they should be blaming their poor work ethic and shoddy training techniques. Bottom line: If you take anything home from this article, it's that you should be taking most, if not all, of your working sets to muscle failure, or close to it, for maximum muscle growth.

The debate is over. Another finding from these two studies is that training with lighter weight done for higher reps appears to be better at promoting muscle growth than heavier weight done for fewer reps. But hold up: There are two problems with these two studies. The first is that these studies only measured muscle-protein synthesis.

Yes, that is an indication that the muscle is in a heightened state of muscle growth. But they didn't measure actual muscle growth over time training these ways. They just looked at a snapshot from one workout. It's a pretty good snapshot, but it still doesn't prove that this will lead to greater muscle growth.

The second problem is that the heavy-weight sets were done with a weight that limited the subjects to just reps. Even the most ego-maniacal bodybuilder typically doesn't train in this low of a rep range. So it really isn't a fair comparison of heavy weight versus light weight as far as what those terms mean for the average bodybuilder. The McMaster researchers finally did a follow-up study to see just how well these light-weight, high-rep sets hold up for instigating real muscle growth compared to more realistic rep ranges.

They had subjects perform one of three leg-extension training programs three times a week for 10 weeks:. Immediately after each workout, the subjects ate a protein bar that provided 30 grams of protein, 33 grams of carbs, 11 grams of fat and 4 grams of the BCAA leucine.

This increase in muscle size was visible in both the slow-twitch and fast-twitch muscle fibers. The take-home point here is that to maximize muscle growth, you definitely need to perform more than one set per exercise, but whether you train in the rep range or the range doesn't really matter as long as you take each set to muscle failure. But before you start thinking that it doesn't matter what rep range you choose, the researchers also measured muscle strength and muscle endurance before and after the week program.

They found that the group training with either one set or three sets of reps per set increased their one-rep max strength significantly more than the group doing three sets of reps. So although training with both heavy weight and light weight can elicit similar increases in muscle growth, they offer different benefits to the muscle's capacity.

The heavier weight leads to better increases in muscle strength, while the lighter weight training induces increases in muscle endurance that the heavy-weight training does not. The real take-home message from these studies is that you should never stick with one rep range for too long. Regardless of how heavy or how light you go, you will be able to increase muscle growth as long as you train to failure. Changing up your loads from heavy weight for fewer reps to lighter weight for higher reps also allows you to increase muscle strength and muscle endurance.

Having greater strength and greater muscle endurance allows you to train with heavier weights and to complete more reps with a given weight, which can help to better influence muscle growth. Regardless of what each rep range offers, the simple fact that you're changing things up helps prevent stagnation to allow for continued gains in muscle size, strength and endurance.

This is known as the "Weider Muscle Confusion Principle" and it works well—now we know why! A great way to change up your rep range is to use linear periodized microcycles, where you start out with lighter weight for higher reps and gradually increase the weight each week until you're down to very heavy weight for low rep counts.

This is similar to my Micro Muscle program aka Shortcut to Size. Or try my Up and Down week plan below, which increases the weight each week starting with reps way up in the range and brings you down to just reps per set.

You'll then reverse the order, reducing the weight each week until you're back to doing reps per set. You can repeat this indefinitely as long as you change up other variables, such as the exercises used and the rest periods between sets. Just be sure to take each working set to muscle failure or close to it. I can guarantee you'll realize new gains in muscle growth using this type of program. Try this plan that changes up your rep ranges every week. You can use any training split you like and any workouts you prefer.

Just keep each set in the prescribed rep range for that week and be sure to take each working set to muscle failure. You can even consider taking the last set of each exercise beyond muscle failure with techniques like forced reps, rest-pause or drop sets. Henneman, E. Relation between size of neurons and their susceptibility to discharge.

Fallentin, N. Motor unit recruitment during prolonged isometric contractions. European journal of applied physiology and occupational physiology. Fuglevand, A. Impairment of neuromuscular propagation during human fatiguing contractions at submaximal forces.

The Journal of Physiology ; Sale, D. Influence of exercise and training on motor unit activation. Exercise and Sport Sciences Reviews. Burd, N. Low-load high volume resistance exercise stimulates muscle protein synthesis more than high-load low volume resistance exercise in young men. Enhanced amino acid sensitivity of myofibrillar protein synthesis persists for up to 24 h after resistance exercise in young men. J Nutr. Mitchell, C. Resistance exercise load does not determine training-mediated hypertrophic gains in young men.

J Appl Physiol. When it comes to rep speed, most people stick with the tried and true slow and controlled pace of about seconds on the positive and about seconds on the negative.

While this is the pace you should keep for most of the time, you should occasionally consider going much slower some of the time and much faster some of the time. Super slow reps can help you build more muscle, while fast and explosive reps can help you build more strength and power, which can help you build more muscle in the long run, and they can even help you to burn off more body fat.

Scientists from the University of Sydney Lidcome, NSW, Australia had males and females follow a biceps training program for 6 weeks using different rep speeds to determine which rep speed on the one-arm biceps curl best increased strength and which rep speed best increased muscle size. One group did one-arm biceps curls using slow reps 3 seconds on the positive and 3 seconds on the negative part of the rep , while the other group did fast reps less than 1 second on the positive and negative part of the rep.

Each group trained with a weight that limited them to reps on the one-arm biceps curl and trained three times per week. In other words, fast reps appear to be best for increasing muscle strength, while slow reps are best for increasing muscle size. Slow reps may increase size better than fast reps due to a greater increase in growth hormone GH and testosterone levels. A Japanese study reported that subjects using slow reps raised GH and testosterone levels than those using faster reps.

Fast reps likely increase muscle strength better because they utilize more of the fast-twitch muscle fibers within a muscle.

These are the muscle fibers that can contract with great speed and strength. These muscle fibers also appear to burn more calories than slow-twitch muscle fibers. So be sure to change up your rep speeds just like you change up other aspects of your workouts. Keep normal-speed reps at the foundation of your training program, using them the majority of the time.

However, also use fast reps for building strength and power, as well to drop body fat. Use slow reps to help encourage more muscle growth. To try a workout that combines all three reps speeds, and therefore all of these benefits, check out my Speed Set Training program in the section below. In the below video, I demonstrate Speed Set Training using standing dumbbell curls two arms at a time, not alternating as an example:. Each Speed Set consists of three different rep speeds, doing five reps at each different speed for a total of 15 reps.

Because of how demanding one rep speed set is, it doesn't take much weight to thoroughly fatigue the muscles. That's why I say it's great for those times when all you have is a light pair of dumbbell available—like when you're traveling and staying at a hotel with a limited fitness center.

Get tweets. Subscribe to RSS feeds. Get article updates in your email. August 09 The most effective rep range for muscle growth? Now what is wrong with the GH hypothesis? Practical Application If anything above makes any sense, then there is no reason to hold on to reps as the best or the most effective for muscle growth. How to Build and Stretch your Calf Muscle? Are low reps better than high reps for muscle growth? Are Low Reps Ideal for Strength? Cardio on Lifting or Non- Lifting Days?

Anoop Thu August 14, Thanks for comenting. Any feedback is appreciated. Get free updates with:. Like us on Facebook.

Thanks for visiting Exercise Biology. About me My name is Anoop Balachandran and I am the owner of this site. Please read more here.