table of contents

  1. what is weight training?
  2. weight training as a stressor and the body's stress-response
  3. rest and recovery
  4. strength development and muscle hypertrophy
  5. lactic acid threshold and muscle endurance
  6. weight training and fat loss
  7. weight training movements
  8. some frequently asked questions / misconceptions

what is weight training?

Weight training is the activity that people do when they go to the gym and perform movements like the bench press, the biceps curl, etc. "Weightlifting" is the actual sport of lifting weights overhead. Powerlifting is the more popular and well-known sport in that respect, and most people who go to the gym have probably heard of the events; the back squat, the bench press, and the deadlift, performed in that order in competition (though there are single-lift and push-pull meets as well). Weightlifting, powerlifting, and weight training have a lot of things in common, i.e. they all involve moving free weights in some way, but they describe different activities. Weightlifting and powerlifting are their own respective sports; weight training is a tool. People who seek to be fit, build a better body, or establish a foundation for general health incorporate weight training as part of an overall health or fitness program. Athletes also incorporate weight training in order to prepare and condition themselves for their particular sport, or to rehabilitate an injury by strengthening the appropriate muscle group.

weight training as a stressor and the body's stress-response

The concept of weight training is based on the principle of progressive overload, which is subjecting the muscles of the body to greater and greater levels of resistance in order to induce a growth response. Weight training acts as a physiological stressor, and the body responds to it by releasing various hormones and chemical messengers to produce the stress-response.

During training, muscles are damaged under the trauma of heavy resistance (the most damage occurs during eccentric contraction, or when the muscle lengthens under tension). "Micro-trauma" is the result of small tears in muscle fiber during weight training, and is the cause for delayed onset muscle soreness, or DOMS.

After training, the body enters a stress-response state in which it is geared to not only repair damaged muscle fibers, but to make them stronger and less susceptible to damage, but only to the level of resistance it has already been subjected to, this is why progressive overload is the driving principle in weight training. In this state, the body catabolizes macronutrients to replenish glycogen stores and the muscles themselves - of particular significance is protein, which has been shown to aide in the process of muscle growth.

Repeated exposure to intense weight training causes the body's metabolism rate to increase. The nutrition it receives is constantly geared toward rebuilding damaged muscle tissue and maintaining lean body mass. An important controller of growth and body composition during this time is calorie intake. If the calories consumed total less than "maintenance," or the level of intake required to simply maintain body mass, muscle growth will generally be minimal, but the body will be unable to store nutrients and will in fact draw from fat stores (the buzz word is "burn fat") in order to maintain lean body mass. If the calories consumed total more than maintenance, muscle growth will be significantly greater (along with some storage of nutrients as fat).

It is important to note that in respect with weight training, the body is in two general states - either in an "active" state during training, in which the muscles are stimulated, or the stress-response state, in which the body responds to the stressor of weight training and repairs and rebuilds damaged tissue. This is why weight trainees are told to make sure they get enough rest or off-time from training. This has been told and written probably about a million times but the body doesn't grow stronger during training, it's the period after training in which the muscles become stronger, after they've adapted to the stressor of training.

rest and recovery

The figure "48-72 hours" is generally given as the time required for muscles to "fully recover" from a weight training session. However, individuals new to the whole gym thing may take a little longer to recover from the unfamiliar stimulus. Also, let me ask you a couple questions - Does the body recover in the same time frame with every single workout? What happens if you workout the same muscle group, let's say, 40 hours later? Are you doing more damage than harm? Are you over-training?

"It takes 48-72 hours for a muscle group to fully recover from a workout." That causes people to think in terms of only individual workouts. I bench pressed Monday, so I should wait until at least Wednesday before I bench again. I'm not saying it's wrong, there's good research behind it - I am saying that it doesn't give the whole picture. It's more effective to think in terms of an overall training period.

Remember that weight training is essentially a physiological stressor. Do you really have to be "fully recovered" from a stressor before being safely stimulated by it again?

Think of another stressor, such as sleep-deprivation. How long can you go on six hours of sleep a night? Like weight training, sleep-deprivation puts your body into a certain stress-response state. You can probably stay reasonably functional for three or four days, I mean it'd suck and you'd want to take naps, but if you really had to, a crisis in the family, a crisis with yourself, work demands, school demands, you could do it without too much trouble.

How long can you go on maybe three hours of sleep a night and stay reasonably functional? If you're like me, probably a day or two.

But eventually, either way you would need a couple nights of much longer sleep (8 or more hours) before you can recover from sleep debt and get back to five hours or less sleep a night and stay functioning. Some of you don't and you probably feel like a zombie all the time.

When you think of recovery from a workout, always think in terms of how much stress you've accumulated. Some workouts are tougher than others - ten squat cleans are going to be a lot harder than ten bench presses with the same weight. The weight is being moved much faster (more force is being generated in less time), and it is moving a much greater distance (more physical work is done). You are going to need more rest from the squat cleans than you are from the bench pressing. Also, at some point, your body is going to need a period of longer rest and recovery in order to recover from the total accumulation of stress.

The best advice I've heard as far as rest and recovery goes is, for every three weeks of hard training, take one week "off." That's not necessarily meaning to stop working out or exercising for that week, but back off on the weights, do some light, easy movements that you've never done before (overhead squatting?), or do other tough, non-weight training workouts like pushing a car, gardening, wrestling or boxing with a friend, etc. The idea is, at some point or another, your body's going to force you to take time off, either from poor performance, over-use injury, or just being burned-out, and it's better to schedule it yourself than for it to come unwanted and unexpected.

strength development and muscle hypertrophy

Two of the many benefits of weight training are strength development and muscle hypertrophy. Let's go over some important concepts related to these benefits.

  1. Motor coordination: This is neuromuscular strength. The muscle itself does not become stronger, but your nervous system "learns" to recruit more and larger motor units - a motor nerve cell connected to a certain number of contractile muscle fibers within that muscle - in a shorter amount of time.

  2. Contractile fiber hypertrophy: This is strengthening of the actual muscle. Muscle fibers recover from micro-trauma and become thicker and more resilient to the amount of tension to which it has become subjected.

  3. Sarcoplasmic hypertrophy: This is the enlargement of the muscle cells that make up muscle fiber. Sarcoplasma is the cytoplasm of muscle cells - it's fluid that carries the enzymes, nutrients, and electrolytes needed for the cell to survive. Because sarcoplasma isn't directly involved in the contraction of muscle fiber (they function as a unit, not individually), sarcoplasmic hypertrophy plays a role in the development of muscle mass, but not the development of strength.

The strength and thickness of the fibers in a muscle are its potential for developing tension; neuromuscular efficiency is what determines how much of that potential can be used to develop force.

It's time to blow some minds.

Different types of weight training can develop different kinds of strength and hypertrophy. Given a particular movement, there's a certain amount of weight that you can lift exactly once, and no more times after that. That's what is generally referred to as a "max" squat, clean, press, etc.

Lifting close to that limit weight is what develops motor coordination. Because you have to use so many motor units to move the weight, your nervous system is going to become more efficient at recruiting those motor units in less time. But because there's not a lot of time under tension, the damage to muscle fibers is minimal, so this type of training is not going to put a lot of muscle on you.

As you start lifting a smaller and smaller percentage of that weight, motor coordination becomes less important because less motor units are required in less time to move it. You can lift these lighter weights a few more times, so now, the muscle fibers are under tension for a longer period of time, and they're undergoing more micro-trauma. When they are repaired and rebuilt, they will be stronger and bigger than before - they will have hypertrophied.

Realize that one workout is not going to make you more neuromuscularly efficient or bigger - repeated exposure, progressive overload, and adequate recovery both from individual training sessions and the total accumulation of training is what brings about these effects.

Weight trainers refer to individual movements as "repetitions" or "reps." They will refer to each effort to move a weight for so many repetitions as "sets." There's some specific, mathematical mumbo-jumbo about how many reps and sets you have to lift a weight to develop a certain aspect of strength, but here's a very general, very pragmatic run-down:

  • In the competition phase of their training (but not year-round), weightlifters and powerlifters will train exclusively for singles, doubles, and on the rare occasion triples - they will lift a high percentage of their max whatever for one, two, or three repetitions. They will "work up" to that weight in certain increments, so maybe three or four sets, they will be warming up. The next couple sets will be "work sets," i.e. they are actually trying, and they'll finish with a big effort, the "big single" or "big double" or etc. for the day. Weightlifters and powerlifters train almost exclusively for neuromuscular efficiency - lifting the most weight possible at their competition bodyweight. If you want to develop motor coordination, emphasize singles, doubles, and maybe triples.

  • A lot of football players (throwers, wrestlers, etc.) who want to develop strength and muscle mass in the off season will also "max out" on some training days, but the bulk of their training will consist of moving a weight for five or more repetitions. Different coaches will assign different workouts, but, fives, sixes, and eights are pretty common. You will probably read the most about "5x5," or five sets of five repetitions, for the power clean, bench press, back squat, etc. The athlete will choose a weight he can lift for five reps without straining. Each workout, he'll add a small amount of weight and attempt to complete 5 sets of 5 reps - progressive overload. If you want to develop strength and muscle mass, lift somewhere in the fives, sixes, and eights.

lactic acid threshold and muscle endurance

So what happens when you start training with a lot more reps than six or eight?

The muscles will experience a much longer period of tension, so the hypertrophy effect should be greater right? Not necessarily. For efficient weight trainers with excellent neuromuscular strength, squatting a big set of 15 or 20 in the 300s of lbs will definitely induce a hypertrophy effect. However, they've developed their motor coordination to an extreme degree, they can recruit a lot of motor units very quickly. Also, 300lbs isn't "record-breaking," but it's still a much larger tension than the human body is used to, close to double bodyweight for the average, gym-going male.

Most people haven't reached that degree of efficiency yet. So what happens when they try to squat a set of 15 or 20?

Somewhere around repetition 10, they're going to experience acute muscle fatigue. It will feel like they can't develop as much tension per repetition; it may even feel like they can't develop any tension at all. They may experience a burning sensation in their muscles. If they keep going to 15 or 20, the burning is going to be replaced by a dull numbness and the perception that muscle contraction becomes increasingly weak.

What the fuck just happened?

Lactic acid is produced as a by-product during muscle activity; as its concentration builds up in the muscle, pH levels decrease, causing that burning sensation. Also, remember from high school biology (if you can) that muscle contraction is an "electric" function. When stimulated by the nervous system, electrolytes travel in and out of a muscle cell and cause a "depolarization" that induces muscle contraction. Lactic acid also serves as an inhibitor for that effect, in that as a metabolite, it interferes with the muscle cell's up-take of the molecules it needs to receive to respond with contraction.

It's the body's natural defense mechanism from damaging itself with too-strenuous activity.

Training for repetitions in the high ranges (beyond 8) can make you stronger and bigger, but the greatest effect of this type of training is in developing muscle endurance, or the ability of a muscle to contract against low-level resistance for an extended period of time. Your body's "oxidative systems" are going to become more efficient at delivering oxygen to your muscles, which will raise your lactic acid threshold since lactic acid is an anaerobic by-product. Some strength and conditioning coaches feel that muscle endurance training would benefit athletes like wrestlers.

Training for "a lot" of reps is generally associated with sarcoplasmic hypertrophy, sarcoplasm swells with more fluid and the metabolites required to fuel muscle contraction. This is not to say that you won't develop any strength, but the main stimulus that the muscles are going to adapt to are many low-resistance contractions over a significant period of time.

weight training and fat loss

Most people don't know this but weight training is one of the more effective ways to control body composition (body fat percentage). Low-intensity cardiovascular exercise such as running, cycling, the goddamn elliptical machine, and aerobics classes can produce weight loss with a controlled diet, but it can also lead to a reduction in lean body mass (muscle).

Weight training works well as part of a fat-loss program because it promotes the development and retention of muscle over other tissue (i.e. fat). In a controlled diet, in which the intake of calories is restricted to a level that results in the loss of bodyweight, the body is not taking in enough food to maintain weight. Because of the physiological response to weight training, the body is also struggling to repair and replenish stimulated muscles. Without enough nutrients obtained from diet, fat stores are broken down to fuel the body, resulting in fat-loss.

weight training movements

There are two types of movements in moving a weight: compound and isolation. A compound movement involves the movement of multiple joints, such as in the front squat, power clean, and overhead press. An isolation movement is a movement that tries to isolate the movement of a single joint, such as a leg extension, a biceps curl, or a triceps extension.

Keep in mind that weight training is a stressor. Movements that move the weight a greater distance and incorporate more muscle groups are going to be the most effective in terms of inducing the stress-response effects of weight training, because generally more weight is being lifted and the force that must be generated is greater - it will have a significant stress effect. Power cleaning something is going to be great training, the body will respond to it very well over a period of a month. Curling a dumbbell with a bicep will probably not be as effective in inducing strength development or muscle growth in the same time period, because the effort and work exerted is so small in comparison.

That is not to say that isolation movements have no use in weight training. However, they are only useful in developing a particular muscle group, rather than the body as a whole. It's going to be difficult to get just big arms, because the arms themselves can't move a lot of weight. It'd be easier, and more useful, to develop a bigger upper body as a whole through the use of the bench press, rowing, and power cleaning, which develop "total body" strength through many muscle groups, and then finishing the workout with isolation movements.

The Arnold that we know today did not become Arnold from curling religiously; it was from lifting weights that a lot of people chose not to (the steroids helped I'm sure, but hard work is the biggest factor in things like weight training) and using a variety of compound movements in conjunction with joint-isolation.

From an athletic-performance standpoint, the top weightlifters in the US aren't breaking US records because they do dumbbell lunges; they're squatting and snatching and cleaning-and-jerking their goddamn hearts out. The top guys are constantly lifting over their bodyweight, and I mean they're moving it from the floor to overhead. There is not a lifter in the top ten who doesn't squat (to the bottom, hamstrings to calves) double bodyweight, some of the lighter guys are either approaching or exceeding triple that.

As far as weight training movements go, nothing replaces hard work.

some frequently asked questions / misconceptions

- yo this node inspired me, how do i get started?

Buy a gym membership or a weight set and get started. Put in hard work, don't strain yourself, and read as much as you can on everything. Former throwing coach Dan John has a lot of good advice for you.

Keep things simple though. Ask a friend who played football or something in high school for some tips and pointers to get you started.

One of the best places you can start, though, is a good powerlifting or weightlifting club. You don't have to compete, but they'll help you out a lot.

- Professor secondchances, I heard that a girl who lifts will get muscular like a guy and she will look like a roidhead :( :( :(

Those huge, muscular, testosterone-sweating guys with 22-inch arms? How long do you think they've been working out? How much weight do you think they can lift? Now how much do you think a girl can lift? Exactly how big do you expect her to get? Some girl bodybuilders can get pretty jacked but you've got to realize the extremes to which they train and diet. We're talking they probably lift like 20 hours a week, get 300g of protein a day, they do the whole supplement thing, I'm sure some of them roid, people are competitive. A girl training casually is not going to post a 300lbs bench and sport Arnold's pecs unless she really, really tries and devotes the majority of her efforts in life towards that end.

Just to spread some enlightenment, look at some pics of the bodybuilding girls in the off-season. When they're prepping for competition they're going to be ripped, very well-defined, very muscular, but that's what bodybuilding is about. In the off-season a lot of them look just like fit, active people who workout.

Maybe they don't fit everybody's taste as far as sex appeal but they're not freaks, they tend to get some negative attention which is a little unfair.

Anyways it's hard enough for a guy to put on muscle; for a girl with lower testosterone levels it's going to be even harder.

- i don't want to get bulky so i don't lift heavy weights, i just want to get tone and defined

This is kind of a body image issue, but honestly, the whole point of weight training is to move weight against resistance that the muscle isn't accustomed to, progressive overload. Lifting weights the muscles can move easily isn't very stressful - the body's stress-response won't be as pronounced.

Another thing, "getting bulky" happens when you eat to get bulky, an ultra-high protein diet and lots of surplus calories. Otherwise, you won't gain weight. The weight lifted is only half the equation to hypertrophy; proper diet and nutrition is the other half.

Putting on muscle past the first few months of lifting is one of the hardest things you'll do in life. You've got to eat more than you want, ensure you intake enough protein, and constantly train at a high level of effort. You're not going to get jacked unless you really, really want to and go way, way out of your way to do it.

- how do i get a six pack

It's generally a reflection of body fat percentage. If you're a skinny fuck then you may not have enough abdominal muscle to show a decent six-pack even with low body fat. Weight train, eat a lot of food (a lot of protein), gain ten or twenty lbs, and see what turns up.

- but i do like 1000s of crunches a day

Most of the direct abdominal movements the general public is aware of are pretty low-impact, some strength and conditioning coaches feel that as a muscle group the abdominals respond the least to training of any kind.

The athletes who I've seen with great abs do a lot of movements that involve maintaining an erect, stable torso in conjunction with the crunches, sit-ups, etc. - football players, sprinters, weightlifters, powerlifters, the lean guys in lower and middle weight classes who squat and deadlift and power clean a lot have got killer abs. That generally means they're pretty muscular all over, too.

- i tried to work out before to get bigger / lose weight and it didn't work for me

The calorie intake thing is not bullshit - if you eat less than your body needs to maintain, you will lose weight. If you eat more, you're going to gain weight. But the important thing is consistency - eating less or more than is required on a day-to-day basis, every day, for a significant period of time.

Some people aren't aware of how much/how little they eat a day. The best recommendation for them is to keep a daily food log and keep track of the calories as best as possible. Add or subtract food day-to-day until the desired effects are measurable (this also means weighing-in at a consistent time - you weigh differently in the morning than you do at night).

Also keep in mind that unfortunately, your metabolism reacts to changes in how much food you feed yourself. When not enough food is eaten, your metabolism will slow down in order to maintain as much body mass as possible. If you start eating a lot, your metabolism will speed up in order to burn as much of the calorie intake as possible. This is why consistency is so important, you've got to keep track of how much you've eaten and how much you weigh from day-to-day in order to figure out how much you've got to eat for the desired effect.

- what is a complex, hyper-advanced training program i should train with

You're probably jumping the gun, buddy. Put in the time first, and post some good numbers or a killer physique, then start thinking about doing the crazy stuff. A lot of people make the mistake of doing some workout that Arnold supposedly did in his prime or doing a Bulgarian gold-medalist's training program. Realize that those guys have already trained for years and attained a level of performance that puts them in the top .001% of the world.

Simple training will take you a long way. If you want to get better at benching, just bench. If you want to get better at squatting, just squat. There's no reason to follow Westside Barbell's conjugate method if you're weighing-in at a buck fifty and still trying to bench 225.

- lifting weights will just get you injured in the long-run

Some people will tell you that squatting will ruin your knees, or that you should only squat to parallel - not true. It's a basic human movement, and if you weren't meant to squat all the way down, why would your hips and knees and ankles allow you to move that way? Usually if you try to move a joint beyond a normal range of motion, it dislocates. People get hurt squatting because they're loading weight that they haven't trained for - this is another one of those things that has been told and typed a million times, people's egos hurt them, not the weights they lift.

The most common injuries I hear about are probably shoulder, knee, and lower back injuries, from bench pressing, squatting, and deadlifting. It's invariably a joint problem, i.e. spraining a ligament, or back flexion, which is associated with lower back injuries. They can be prevented by lifting weights that can be controlled, and (this is another one of those goddamn phrases that have been told and typed a million times) "maintaining good form." Straining to lift with your shoulders hunched a certain way or your back folding a little during one workout probably won't kill you; it's repeating this behavior consistently that will eventually lead to an unnatural joint articulation and injury.

Some movements, such as the behind-the-neck press and upright row, have a reputation of being "bad" for you, and there's some evidence to back it up, but again I'll ask the question - if your joints can move that way naturally, why would that movement hurt you? For every story I've heard about someone ending up in the operating room for pressing behind-the-neck, there's also a story about a thrower who pressed behind-the-neck something like 330lbs in the off-season and then broke a record in competition.

Let me say one more thing on the subject: how many times have you heard about something being bad for you, then you try it, and you realize it's only bad for you if it's done improperly? I'm not talking about drugs or alcohol though. Certain kinds of sex are probably more relevant.

- working out isn't worth it unless you go to the very last rep possible, and then some, and you're dead sore the next day

It is a really great feeling to feel completely destroyed, but delayed onset muscle soreness isn't the best indicator of progress. It's only an indication of muscle fiber damage, not muscle fiber growth.

Athletes training for performance don't kill themselves every workout; they know the benefits come from the total, cumulative effect of training, not just one workout. They'll train hard, but their coaches understand that a stressor like weight training is only good if the athlete recovers from it in a reasonable amount of time so he can train again, and again, and again and post better and better numbers.

- hey so i'm reading some more stuff about lifting - there's a lot of conflicting information :(

Yeah it sucks. A lot of the information you're going to find, even published stuff, is going to be bullshit. Best sources of info are college athletes, particularly track runners, jumpers, throwers, etc. If you've got a good football program the football players might be helpful. A lot of good things are said about track coaches.

A weightlifting or powerlifting club, like I said before, are really good places to start, even if you don't compete. Weightlifting in particular is desperate for involvement, they'll train anybody, and I might be biased but weightlifting is the best weight training related sport to develop good athleticism and good training habits.

Guys in a commercial gym who try giving you advice are going to be hit-or-miss. There are some legitimately strong guys out in public, but they are very few and far between. They are probably on the same level as US personal trainers as far as consistency goes - they either know their shit or they are completely full of shit.

Nothing beats experience though, your first few months of training are really going to be you learning what your body responds to.

Sources Cited:

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  • "Strength Training for Women: Debunking Myths that Block Opportunity." William P. Ebben and Randall L. Jensen. The Physician and Sportsmedicine. Vol 26. 1998.
  • Enhancing Recovery: Preventing UnderPerformance In Athletes. Ed. Michael Kellman. 1st ed. Human Kinetics Publishers, 2002.
  • Human Anatomy & Physiology. Marieb, Elaine N. 7th ed. Benjamin Cummings, 2006.
  • Exercise Physiology. Powers, Scott and Howley, Edward. McGraw Hill, 2003.