Cordyceps sinensis has been used as an herbal tonic in China for hundreds of years. It is used to strengthen your energy and will also improve athletic endurance. Chinese tonic herbs such as cordyceps are used to improve longevity and also serve as anti-aging remedies. Cordyceps can be taken long term to improve endurance and energy levels. Some ailments that cordyceps can treat: fatigue, asthma, enuresis and back pain. Cordyceps works by strengthening the energy of your lungs and kidneys. These organs are responsible for energy production in your body. Taking herbs to strengthen them will significantly improve your energy levels. Cordyceps is also useful for your libido. In Chinese medicine, your libido is often affected by low energy levels in your kidneys. If you have low kidney energy, you will not make enough hormones to function in a health way. Cordyceps is one of the best herbs that you can take to improve your health.