Heat cramps happen because of loss of fluids and salt when we do exercise or excessively sweat. This is treated by rest and drinking water and electrolytes to replenish what we lost
Heatstroke happens because we overheat in the sun. This is treated by getting out of that heat into the shade or closed space. Then we need to cool down, drink water and maybe even remove some layers of clothing to help the body cool off.
Strength training makes you stronger and fitter. It also protects bone health ans muscle mass. Helps keep the weight off for good and helps you develop better body mechanics.
The principle of progression states that you should increase overload, which can be achieved by using FITT when your body adapts to its present routine. The specificity principle states that only targeted exercises will improve specific fitness goals.