How you train – effort, volume, frequency, form, etc. – is far more important than the equipment you use, or whether you use equipment at all. That being said, there are major differences between training with bodyweight and weights and both have advantages and disadvantages.
The biggest advantage to bodyweight training is most exercises can be done almost anywhere since all that is required is adequate floor space, and various types of chin ups and pull ups can be performed anywhere there is a reachable bar, or if you’ve got a strong grip, anywhere you can securely hang a strong towel or thick piece of rope. It is both convenient and time efficient.
Whether a person travels frequently where they don’t have access to weights, doesn’t have equipment at home, can’t or doesn’t like going to a gym, or just prefers to train at home or outdoors, they can still train effectively performing just body weight exercises.
A variety of portable apparatus are now being sold for body weight training but most are unnecessary and overpriced. They are often marketed on the premise one needs to perform a huge variety of exercises, when all that is actually needed is a few basic movements that only require a few square feet of flat ground and something to hang from. Most of the more useful apparatus for bodyweight training (parallettes, chin up bars, parallel bars for dipping) can be easily and inexpensively constructed or found in some form in the local playground.
The biggest disadvantage to bodyweight training is resistance progression is not as straightforward or as easily quantified as with weight training.
As you become stronger and better conditioned you must increase the resistance you work against during exercise to stimulate further improvement. Resistance – the force your muscles work against during exercise – is the product of a variety of factors, the two biggest being mass and lever.
Resistance progression with barbells, dumbbells or machines is simple and easy to quantify, record, and compare over time. As you become stronger you increase the weights used – the mass – proportionally. The movements (levers encountered) do not vary significantly.
With bodyweight training the mass – your body – does not increase in proportion to your strength. If you’re losing fat your body is providing progressively less resistance, and muscle mass does not increase in equal proportion to strength (e. g. you don’t gain 10 pounds of muscle mass for every additional 10 pounds you can lift on average). To increase resistance without resorting to weight belts or vests you have to increase the lever the muscles are working against. This is accomplished by performing progressively more challenging variations of an exercise or progressively more challenging exercises for each muscle group.
It is possible to become extremely strong and muscular using body weight exercise alone. You’ve got to be pretty strong to perform multiple, strict repetitions of one-armed chin ups or push ups, one-legged squats, or handstand push ups. A disadvantage of using lever variation instead of weight increase to progress resistance is every new exercise is a new skill to be learned and some bodyweight exercises, particularly unilateral (one-armed or legged) exercises can initially be as much or more of a skill challenge than a strength challenge (I recommend being very cautious with unilateral exercises as the risk of injury is greater). By comparison, with weights once you have learned and developed proficiency in the skill of performing a particular exercise you can focus more on simply becoming stronger.
Some claim this is an advantage and that these skills will translate to other activities. While the strength gained from bodyweight exercise will transfer to other activities, skill is very specific and balance or exercise movement skills do not transfer to other balance tasks or movements.
Weight belts and vests provide an effective and more easily quantified form of resistance progression, but these aren’t always practical for those who choose to train with bodyweight due to travel requirements or who train outdoors away from home. Lugging around a heavy weight vest or a dipping belt and weight plates defeats the purpose.
My personal preference and recommendation for those who can is to train primarily with weights, whether barbells, dumbbells or machines. Once the basic skills are learned more focus can be given to the effort put into training, and resistance can be increased in a more consistent, measurable and relatively precise manner. Even then an occasional bodyweight workout can be a fun challenge or change of pace, especially outdoors in good weather. For those who train primarily with body weight the occasional workout with weights will provide a more objectively quantifiable benchmark of strength increases.