If i want to transfer money from euros to pesos, and its asking me the payment currency, what does it mean? The currency from its taken or recived?
It is easily available; you can get it from energy drinks, coffee, tea, coke. It's extremely effective in increasing your energy before a workout because it is such a fast acting substance. Caffeine increases your mental alertness. However, a word of caution, caffeine only offers a temporary boost of energy.
The best way to keep your energy levels up during periods is to eat foods which give you natural sugars such as bananas, dates, grapes, mangoes, etc. Apart from these foods, whole grains like oats, jowar, ragi, brown rice also help provide a great deal of energy. Sprouts and salads should also be a part of your diet.