Dumbbells

Why

Weights

Good workout. Fun. Vanity.

Free Weights

Helps develop control muscles.

Dumbbells

Ideally, a whole range of equipment would be available, but when we start applying real world constraints, that's where dumbbells shine.

As Good

Head to head, each has their advantages. I believe that a barbell will develop pure strength faster, but dumbbells develop a wider range of motion and better control. Whenever I do a similar exercise on a bar, I can lift about 10% more than what I do with dumbbells.

Almost any exercise you can do on a bar you can do on dumbbells, but the reverse is not true. You can get about 150lbs on one dumbbell, for the equivalent of 300lbs on bar (330lbs if you accept my 10% assertion). There aren't many exercises you're likely to max that out, particularly if you're just starting.

Practical

A cheap set of plate base dumbbells is going to cost around $100 and will cover you for quite a while (more on this later). When you're ready to expand, you can buy plates as needed. An exercise bench is going to be around $50. So your startup cost is going to be around $150. An area of 5'x5' should be plenty when you're exercising (though you may need tall ceilings). And the whole thing will fold up into a small area when it's put away.

In comparison, to do a bar workout you'll need a bar, rack, bench and plates. This will require a large permanent setup and will probably cost at least $1000.

How

There are lots of approaches, this is what I've learned works for me, and I think it would work for most people.

I don't plan rest days, having a family, job, social life and a number of hobbies, I can't always make time. So when I can I work out. I do tri-sets; rotating between 3 exercises with little rest. I find this to be a good balance allowing me to get in a decent workout in a short period of time (as little as 20 minutes). I do 3 sets of 3 exercises and 6-8 reps. I try to keep the load so that I can just barely finish the last 3 sets and I can feel burning after I'm done. I also try to do a total of one more rep each time (that's one absolute, not one more per set) and when I can do 8-8-8, I increase the weight and drop down to 6-6-6.

Technique

This is the most important takeaway - technique is crucial. Good technique avoids injury and increases gain. There are ways to cheat that will let you lift more than you can with good technique, but they will plateau quickly. Each exercise will have it's own nuances that need to be researched. But there are a few universals.

Concentrate on the primary muscle, not the weight. To the greatest extent possible, make it so that only that muscle is moving and keep it under as much tension as you can while moving the weight at the correct speed.

Speed is, not straight forward. The effect is that you should be going slow, but this should be a by product of good technique. The barbell should never have much momentum. On the contraction, you should be pushing hard against the weight. If the weight is moving quickly, you need heavier weights. But relaxing the muscle is more important. It should take 2-3x as long to release the muscle. Muscle experiences more "activation" controlling and absorbing load that generating force.

These two in combination are critical. Focus on the primary muscle, contract hard enough to challenge the muscle, but not put any momentum behind the weight. Keep the focus on that muscle, during relaxation, it should still be the only muscle moving. Stretch the motion over 2-3x as long as the contraction took.