I don't see any muscle at all in my arms ; I'm 98KG , with BMI of 28.
Is it possible to get some improvement using dumbbells only at home ?
It is a mystery to me how people build their muscles , is there any technique to follow ? Or is not possible for Obese people ?
There's a pretty good answer here that you may want to consider. It specifically is talking about at home exercises, so I'll let that speak for itself. If you need any help with what those exercises look like, check out exrx.net.
Is it possible to get some improvement using dumbbells only at home ?
Yes, although I think you'll find that a few other cheap pieces of gear will make a huge difference. Tack on a pullup bar and a kettlebell and you'll have a formidable home training system.
It is a mystery to me how people build their muscles , is there any technique to follow ? Or is not possible for Obese people ?
If you want the most effective methods for strength training and you're starting from a fairly novice prospective, you will get phenominal results from something like Starting Strength or Strong Lifts 5x5. Those are barbell programs which will require access to somewhat expensive gear. You'll either need to buy it yourself, go to a properly equipped gym (most are not), or have a friend who has gear like that.
A properly run home fitness program can be very effective, but it will never be on par with a barbell strength training program (like the fore mentioned Starting Strength or Strong Lifts 5x5.).
I would say start with your diet and simply increase your overall activity levels. So eating cleaner, probably eating less (although I'm not a fan of caloric deficits by not eating enough). And start by walking every day for like an hour or something.
The exercises I think are the most beneficial are the larger compound ones, squat and deadlift. These do require technique though and if you don't want to spend the time and energy to acquire this bodyweight exercises may be the way to go.
About the arms question: If that really is your only goal, just curl until you can't curl no more.
Is it possible to get some improvement using dumbbells only at home ?
Improvement is always possible through consistent dedication to a routine. If you're willing to stick with one here is what I would recommend. Go to Bodybuilding.com's Arms Workout Database and pick something labeled "beginner" like this.
It is a mystery to me how people build their muscles , is there any technique to follow ? Or is not possible for Obese people ?
It is very possible for obese people to build muscles - don't let your current body deter you from the body you want! The secret is consistency and determination. Having a diet for optimizing muscle building will also help. There are many great questions on here about that and if I had one off hand I would promote it. Please search this SE for one.
Most importantly, do not give up. Progress is slow and at times painful, but it's not going to be easy. Its going to be worth it.
