When it comes to sweating when exercising, there are a few myths and misunderstandings to be aware of:
Myth #1: "If I work out a lot, I'll lose weight."
Fact: I suppose this is true in part. However, the weight you lose is water weight, not fat weight, and it will be restored when you rehydrate.
Myth #2: "If I sweat a lot, that implies I'm not fit."
Fact: Sweating is a method to thermoregulate (i.e. regulate your body temperature). Some individuals are more effective than others at dispersing body heat, which is NOT related to fitness levels.
When you exercise, your body generates heat (when muscles contract, the fibres glide over one another, causing friction), and there are four ways to release this heat. Radiation, convection, conduction, and evaporation are all examples of heat transfer. Sweating is classified as evaporation. However, if it is dripping off you, it is not evaporating and therefore is not helping you cool down. You will benefit from adding some convection (movement of air) through a fan to assist this along since when airflow is introduced to a wet body, and it cools quicker than when it is added to a dry body.
Myth #3: "If you're not sweating when exercising, you're not working hard enough."
Fact: This is also false. Myth 2's explanation is the same.
Your body loses up to 1.5 litres of water each day and much more during intense activity in a hot climate. Aim for 8 cups or 2 litres of water each day (more if you exercise) to stay hydrated.
Important note: Fluid intake may also occur while eating foods containing water, such as fruits and vegetables, which adds to your daily need.