Since early times there has been a belief that if we exercise or rather if we sweat we burn (consume) our fats.
A lot of people believe the concept that excess calories leads to weight gain and hence burning calories will help to lose weight
Somehow this concept was so much accepted by people that we saw many coming up with hundreds of workout programs and also their so called special ways of losing fats.
People started using full body vibrators and sauna claiming that they mobilize fat and reduce weight by inducing sweating.
Some people still believe that when you sweat you use up your fats, Let's understand why this is not true.

When we exercise our muscles perform work, in doing so they consume energy and in turn produce motion and heat.
This increase in the body temperature causes sweating which helps to reduce the body temperature.
Muscles for their activities primarily consume glucose and glycogen within our body not fat.(pls remeber this!)
The human brain completely depends on blood glucose for its functions and hence the muscles have to spare some of this glucose for the human brain.
An individual can surely undergo long durations of physical exertion for which the body cannot provide adequate glucose. Thus the muscles switch over to glycogen (stored in the liver and the muscles) for their source of energy.
Now fats are an excellent source of storage of energy but they are not a fast source of energy. When we workout we need a good & a fast source of energy which is glucose & glycogen rather than fats. So we end up consuming our glycogen stores (which are large enough) and unfortunately our fats remain as they were.
When we exercise we force our muscles to work beyond their existing capacities and thus we inform them that they need to be stronger and have to perform better. Thus the muscles undergo enlargement (hypertrophy) and become competent for the next schedule of the workout where we force them to work even harder. In this way exercising causes gain of our muscular mass causing gain in muscular weight and not fat loss.

The most basic exercising is to burn fats and to consume energy .
Obviously people aim to create an energy deficit and expect that because of this their fats will be used up:) .
Food is the other part of the equation and so if you continue to eat normally you will eat sufficient calories that your body needs to build muscle and there will no no shortage of calories and hence no weight loss!
So we now clearly understand that without diets no exercise regimen could possibly work!
One should understand that muscles require a healthy diet for their growth which is stimulated by the workout. When this supply of required dietary foodstuffs is not available the person may experience malaise, exhaustion and even fever.
This indicates that the body is literally being pulled in two opposite directions; this is in no way going to make you lose fats in a healthy way and should thus be avoided.
Even if you do manage to lose some weight it would strain your body.
The whole existence of gyms and exercising was established for the purpose of making robust and bulky individuals and not to lose weight. It is a mere waste of time & resources to exercise in an attempt to lose weight.
Gyms should be used when one needs to build muscles.

When you exercise regularly your basal metabolic rate and dietary requirements remain increased. Metabolic Rate is the sum of Anabolic (uptake in simpler terms) and Catabolic rate( expenditure) so if you consume more and spend more your BMR increases but you would not lose weight.- because you now eat proportionately more
One question that we need to ask is when we start exercising our energy needs increase so will our hunger remain the same?
- The answer is obviously no. The body increases the absorption and we only lose weight for the time that the body takes to adjust to the change and when we discontinue exercising the exact reverse sequence of events take place and we gain weight.
As you stop your exercising schedule you reduce the energy requirement of your muscles but your body continues to absorb more calories from the food you eat. Hence what follows is a weight gain due to accumulation of these extra absorbed calories and one ends up with even more weight before they started exercising.
Thus if one wants to indulge in regular physical exertion it should be taken care that he/she continues it for long period and there is no discontinuation so that they don't end up gaining fats when they stop exercising.

Mostly all diets except a few like keto & paleo look at cutting down on fats.
Without diets no exercise regimen will deliver results.
Without fats in your meals and with the extra weight on your body there is a very high probability of causing long term damage to your joints especially the knees.
Once knee pain starts any form of exercise becomes painful and difficult.
Think thoroughly whether your trainer understands the amount of load a overweight person puts on his/her joints when he exercises.
Our joints are subjected to 10 times the normal force when we jump ,with 30kg extra body weight you put an extra force equivalent to 300 kgs on your joints. Slowly your joints will give up!

All forms of movement like jogging,jumping, running are to be strictly avoided.
You can try some breathing exercises to increase your lung capacity so that you do not become breathless.
Some basic yogic postures can be tried if they do not put unbearable strain on your joints and body.
Remember it is your body and if anything goes wrong your trainer dietician will not be able to undo it!
Exercises have their own uses but not to lose weight!
Sop believing that you are overweight because you are lazy! Actually it is the other way round - Your weight might be making it difficult for you to do stuff and hence you might be feeling lethargic