It is generally not recommended to engage in heavy weight lifting while fasting, particularly if you are fasting for an extended period. When you fast, your body is in a catabolic state, which means it is breaking down stored nutrients and energy reserves to use as fuel. During this time, your body may not have enough energy to support intense physical activity such as heavy weight lifting.
Furthermore, weight lifting while fasting can lead to muscle breakdown, which can undermine your fitness goals. Without proper nutrition, your body will begin to break down muscle tissue to use as energy. This can result in a loss of muscle mass and strength.
If you want to engage in heavy weight lifting, it is recommended that you eat a balanced diet that includes carbohydrates, proteins, and fats to fuel your body before and after your workout. It is also important to stay hydrated and replenish your body with nutrients after exercise.
It is always best to consult a healthcare professional or a qualified fitness instructor before making any significant changes to your diet or exercise routine.