1. If you're starting out (read: don't yet know what you're doing) then optimize for not getting injured. If you haven't done any weight lifting then you'll get results even if you start out slowly.

2. Optimize for likelihood of you not quitting. If you manage to stick to whatever plan you make you can always make adjustments where necessary. Risk of quitting is the #1 bottleneck.

3. Personally, I think you shouldn't look for supplements until you feel you're reached a ceiling with regular workouts. Starting with a strict diet (measure everything) is a good idea if you're serious about this.

By far my biggest piece of advice would be to not worry at all about optimizing anything until you've first gotten into the habit of regular work outs, and actually enjoy it. Only then should you start optimizing in other ways. The biggest obstacle is always sticking with it.

For me personally this means I lift while watching the Daily Show and Colbert online. Regular 4-days a week at 45 min each day, and it's enjoyable. I can change the time of day I work out, or even what days of the week I do it, but I have to get in some reps to keep up on the comedy-news. Find something you want to do regularly to tie it to.

Also, stretch plenty, before during and after. Don't neglect your neck.

How to structure work-outs. Should I lift as much weight as possible or do more repetitions at lower weights?

High weight, no doubt. Aim for ~8 Reps. Focus on exercises that use multiple muscle groups. ie. Squats, bench press, lat pull down.

How should I trade off frequency of gym visits against length of those visits?

Low frequency. Give yourself time to recover. Don't make the length too high either. The sets you do should be intense. You should be as exhausted as possible after you finish them.

What supplements should I take?

'Roids, if you are optimizing for physique (but probably not if you are optimizing for, well, life in general). More sensibly supplement protein. Play with some creatine if you are enthusiastic, particularly if you are into the appearance boost.

Book recommendations:

• another vote for "Starting Strength" by Mark Rippetoe
• "5/3/1" by Jim Wendler. Available here: http://www.flexcart.com/members/elitefts/default.asp?pid=2976

Answering your questions:

1) It doesn't matter that much what you do, as long as you stick with the basic, multi-joint movements (see below); what's more important is that you do it consistently for a long period of time (i.e., years), and you train progressively harder as you make progress. That said, you need to avoid injury. Training with weights near your one-rep max is riskier as a beginner, especially without a coach. I like the set/rep progression laid out in the 5/3/1 book listed above. I've made good progress on it after doing regular weight training for 15 years; it's difficult to make progress at that "training age", so it should work even better for a beginner.

2) In general, you should strength train at least twice a week but not more than four times a week. This does not include conditioning or mobility training, which you should also do.

3) Don't bother with supplements. Spend your money on a clean diet with lots of protein and you'll be fine. Since you probably won't take this advice: creatine monohydrate seems to have the most evidence in favor of its efficacy, but the effect is still relatively small and seems to vary between users. I haven't noticed a difference when using it.

Remember that there are only a handful of great movements: squat, deadlift, bench press, overhead press, pull-up, push-up, dips, rows, power cleans. Consider the barbell, dumbbell, and bodyweight variations of these and you will have plenty to do without doing a bunch of exotic isolation work.

If in doubt:

Monday: Squat, Bench, Pullups Thursday: Deadlift, Overhead Press, Rows

Three other days: run hills, steep and hard. Two days: rest

My advice is get the book Starting Strength by Mark Rippetoe. He:

• introduces 6 major lifts
• explains why these are the lifts you should be doing
• explains in detail the proper way to perform the lifts with common mistakes, how to spot them, and how to fix them
• explains why, biomechanically, the suggested form is the proper form
• explains how to put these lifts together into a fitness program, and when to stop that program and move on to something else

I was skeptical of the proposed program because I had already been lifting for a couple years, and I found a lot of the suggestions unintuitive. However, after two independent sources told me it was a good program, I started doing it. After 8 weeks I was able to bench press 77.5kg, whereas before I had been stuck for a long time around 70kg. All of the lifts also felt more comfortable / safer than they had before (due to changing my form to match the guidelines in the book).

There is also a Starting Strength Wiki that has lots of good videos / summaries of the information in the book (but the book is way more details / useful, at least for having proper lifting form).

Perhaps you should read a book written by experts in the field. Fahey, Insel and Roth's Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness seems to be one of those.

The best research on work-out composition I've found so far is this survey: http://www.motleyhealth.com/strength/weight-training-intensity-or-volume-for-bigger-muscles (links to the studies at the bottom).

This study supports the use of protein supplements but falsifies the hypothesis that timing matters: http://www.ncbi.nlm.nih.gov/pubmed/19478342

Most of the advice here is really bad. First, any exercise will increase your fitness if you haven't been exercising. After that, what to do depends on what you want to achieve.

Don't try to increase your strength and endurance at the same time. There is pretty strong evidence that exercising for one tend to block increases in the other. If you want to increase both, exercise for strength then when you reach your goals there, switch to endurance training. The one time you may want to do intermediate weights and reps (the maximum weight you can lift for 10-12 times per set) is if you are trying to "bulk up", to add muscle mass to your body.

For strength exercise hard and less frequently. Two or three sessions per week, three exercises per session (best combination is bench press, deadlift or squats, and bent rows or chins), with the most weight you can handle for five repetitions, and do 5 sets, spaced at least three minutes apart, of each exercise.

That is, for example, 5 bench presses, rest 3-4 minutes, bench presses, wait, BPs, rest, BPs, rest, BPs, rest, Squats, rest, and so on. The best gains will happen doing this three times a week.

Once you reach your strength goals, the simplest method to increase your endurance is to maintain the weights and start increasing your reps. Switch to more repetitions per set, but fewer sets and with shorter rest periods between them. You can also begin adding minor exercises, such as curls and calf raises and so on since you want to exercise for longer periods now. Also, for endurance, you should increase the days you are exercising to 5 or 6 days per week with a "split shift", doing chest and shoulders one day, arms and upper back the next, and lower body on the third, then repeating.

You do not need supplements if you are eating a reasonable diet.

Getting sore is a decent indication of how stressed your muscles were.

No, getting sore is an indication of your "total lift" - that is the sum of the amount lifted and how many times. For example, deadlifting 300 pounds 6 times gives a total for that set of 1800 pounds. The greater your total lift, the more likely you are to be sore; and since you can lift 70% of your maximum lift far more times than 90%, you will usually get more sore doing endurance training than doing strength.

Brian Sharkey, Fitness and Health (the earlier editions were titled Physiology of Fitness)

Jim Johnson, Treat Your Own Rotator Cuff and Treat Your Own Knees

and quite a few bodybuilding and strength training books over the decades.

I found reddit's r/fitness 'fittit; a useful resource when I started exercising more seriously a few months ago. Has the beenfit of being gnerally well researched and tested, but not trying to sell you anything (which seemed the case with most obvious fitness sites). Heres a link ot their general faq which is pretty good, http://www.reddit.com/help/faqs/Fitness#Weights

I haven't bothered to keep track of sources, but everything seems to point towards the same conclusions.

• Strength gains go way up with the level of stress on your muscles (but unfortunately, so does the chance of injury). Lower reps, extra reps with spotters, negatives, and especially constant velocity machines are good for this.

Getting sore is a decent indication of how stressed your muscles were.

Studies have shown that more than 1 set doesn't help, but that's only because they use people that haven't been weight lifting and their muscles get plenty torn up after 1 set. More sets can help if you've been doing it for a while.

More reps doesn't build strength so much, but will add more energy storage to your muscles so that you can do more reps (bodybuilders optimize towards building muscle in this way)

• at first, it takes very little time to get way too sore. I only spend about a half hour at the gym, but since I lift heavy weights/low reps and don't waste time (keep my heart rate high), I can get a full workout and be sore all over. I also find it more fun this way.

You can hit diminishing returns after lifting one muscle too much in one sitting or too soon after lifting, so just use soreness as a rule of thumb and don't exceed either of those bounds.

• Creatine, and depending on your diet, protein. We're already almost full of creatine (unless you're a vegetarian, then even your brain suffers), but topping off can help push out a couple more reps and stress your muscles a bit further.

1) Optimize for not getting injured by doing bodyweight exercises.

2) Do slow pull ups. Graduate to pull ups with weighted backpacks, fewer fingers, etc.

3) Run up stairs. Real stairs (or hills).

Hypertrophy Specific Training lists research that supports their training regimens.

I found this to be illuminating, although it has all the flaws you would expect from a magazine article (sub-par documentation, crummy story:information ratio).

The 4th page has a really interesting chart with different workout structures for different goals.

starting strength.

drink milk.

by the time you stop getting gains through this method you will be in amazing shape.

It seems to me there is pretty solid consensus on sites like bodybuildingforums about how to start lifting. Read Starting Strength, eat protein. Most of all, experiment with work out schedules that work for you.

Use whole body exercises. My detailed workout-structure called "The Big Five" is:

1. Seated Row, 2. Chest Press, 3. Pull down, 4. Overhead press, 5. Leg press. I use machines because you can exercise with very high intensity and don't hurt yourself. Train with very high intensity.

-Don't try to imitate Bodybuilders who train several times per week. Their bodies are genetically abnormal and their muscles can recover much faster than the ones of "normal" people.

I recommend articles by Chad Waterbury and Dan John to start, which you can find on www.t-nation.com (which is a quality resource in general). Dan John tends to recommend simple, effective strategies, and Waterbury writes a lot addressing your first and second questions.

A great place to start, this article by Mark Rippetoe: http://www.t-nation.com/free_online_article/most_recent/most_lifters_are_still_beginners

Eric Cressey and Christian Thibaudeau write great stuff, if you're into a more complicated approach.

Also I agree strongly with Zed's point 2.

I agree with Zed's point 3. about supplements sort of. I think the exceptions are (1) "peri-workout nutrition" about which there are many complex strategies but you can keep it simple, say a whey protein & gatorade shake before or after (or both) your workouts, and (2) things often lacking in a modern diet or lifestyle: fish oil (or some other way to get omega 3) and vitamin D seem to be the most frequent recommendations.

In this thread: massive amounts of other-optimization.

Dear OP: As with every other health-related, low-evidence area: experiment, record results, update on data.