Since it is high in antioxidants, green tea is believed to detoxify an abused liver and relieve hangover symptoms. However, green tea was also found to cause liver toxicity in certain studies. Hence, consult your doctor before using green tea for this purpose.
The catechins in green tea have been found to increase endurance capacity and energy levels : https://www.physiology.org/doi/abs/10.1152/ajpregu.00693.2004
Where To Buy Green Tea?