It is generally not recommended to take pre-workout supplements twice a day. Pre-workout supplements are designed to provide a boost of energy and focus before a workout, and they often contain stimulants such as caffeine, which can cause negative side effects like jitters, anxiety, and difficulty sleeping if taken in excess.

Taking pre-workout supplements twice a day could increase the risk of these side effects, as well as potentially harm the body's cardiovascular and nervous systems. Additionally, it is important to follow the dosage instructions on the product label and not exceed the recommended amount.

If you feel like you need a boost of energy for a second workout later in the day, it is recommended to use alternative methods such as proper nutrition, hydration, and rest to enhance your performance, rather than relying on supplements.