: Dumbbell effectiveness I am a 14 year old male. I am overweight and weigh about 60 kg. My height is 5feet 5inches . I want to develop muscle and loose fat for which I have bought a pair of fixed dumbbells 3 kg each. Can anyone

For fat loss and maximum muscle gain you will have to do compound exercises 3-4 times a week combined with proper nutrition. Have a look at this exercise

You can also do the following exercises with dumbbells however you might need some more dumbbells with different weights to target different muscles of your body.

Dumbbell Bench Press
Bent Over Dumbbell row
Dumbbell Flyes
Arnold Dumbbell Press
Dumbbell Alternate Curls
Dumbbell Alternate Hammer Curls
Dumbbell Squats
Dumbbell Lunges
Dumbbell Romanian lunges
Dumbbell Shrugs

Just do a google "image search" of the above exercises and you will be able to understand how it performed.

Combine the above exercises with any kettlebell movement with high intensity and you have a perfect combination for fat loss and muscle gain.

Remember when it comes to weigh loss,gym is only 30% rest is nutrition.

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In order to lose weight, you need to be in calorie deficit. According to your parameters, your daily calories intake for functioning is around 1950-2000 per day, so as long as you'll consume less, you lose weight. When performing aerobic training (running, swimming, cycling, etc) you burn more calories and thus your calorie deficit increases. Strength training will also help for two reasons:

Muscles require more calories than fat for maintenance, thus your required intake increases.
You burn calories during strength training as well (though much less than in aerobic training).

There are more parameters to take into account (for example, body adaption), but that's the general idea. You don't have to perform any sports in order to lose weight, but it definitely helps, and has more positive effects on your body.
In order to develop muscles, you need to stimulate your muscles, cause them damage and thus encouraging your body to support them and make them bigger and stronger. This is also not a simple topic to sum up in one paragraph, but my main suggestion for you is to have a plan. The web is full of beginner's plans, and some of them may be even bodyweight-based.

As long as you're not going to the gym, these are (in my opinion) the most essential bodyweight exercises. Each of them has dozens of versions:

Pushups
Pullups
Planks (rather than crunches, though you can still do it)
Bench dips

Find a version of each exercise that you're able to perform, preferably at least 8 reps. For example, here's a video of 16 pullup variations, from easy to insane. Find your level in these variations.

If you wanna use dumbbells wisely, one set is not enough in the long term. You should build your own set, or, which is much easier, register the nearest gym.

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With 14 I would not worry about gaining muscle. Just do cardio (running, cycling, swimming) for times up to 1h or more. Start with 20min and work your way up.

You can start building muscle when you are 16-18. Testosterone levels are low at your age which won't yield noticeable results, because building muscle is even in the optimal age range a really slow process.

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