Increased Physical Performance 
According to research in the Journal of Dietary Supplements, supplementation with Cordyceps militaris may yield positive effects on physical performance in individuals participating in high intensity exercise.
Researchers found that a supplementation period of one week had minimal effects on physical performance. However, a three-week supplementation period with Cordyceps militaris resulted in “significant improvements” in maximum oxygen consumption (a measure of the body’s ability to uptake and utilize oxygen during intense exercise), ventilatory threshold, time to exhaustion and relative peak power output (calculated as the maximum output achieved during the test divided by body weight). Researchers believe that greater benefits may be seen after supplementing for a longer period of time. However, additional studies are needed to establish dosage for maximal benefits[1].
Improved Respiratory Health
“Some studies suggest that cordyceps may support respiratory function and may be beneficial for conditions like asthma and chronic obstructive pulmonary disease (COPD),” says Dr. Kim.
A 2019 systematic review and meta-analysis in Evidence-Based Complementary and Alternative Medicine considered the effects of Cordyceps sinensis on individuals with stage two (moderate) to stage three (severe) COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD).
Researchers found that Cordyceps sinensis appeared to have positive effects on respiratory parameters, indicating that it could improve exercise tolerance and quality of life in some individuals with COPD. However, strong conclusions on the effectiveness and safety of the fungus are lacking. More comprehensive research is needed to fully validate the respiratory benefits of Cordyceps sinensis[2].
Improved Immune System Response
Research indicates cordyceps may stimulate certain immune cells, such as peripheral blood mononuclear cells (blood cells that contain a single round nuclei, including immune cells like T cells and B cells), thereby bolstering the body’s immune defenses. Some evidence shows that cordyceps may both strengthen the immune system and suppress it due to its adaptogenic nature, which may prove useful in circumstances like following an organ transplant or in individuals with autoimmune conditions. 
Reduced Inflammation
“There’s some evidence to suggest that cordyceps may have anti-inflammatory properties that could be useful in managing certain inflammatory conditions, such as inflammatory bowel disease (IBD) or arthritis,” says Dr. Kim.
Limited research suggests that cordyceps may help prevent the production of inflammatory cells, leading to a potentially positive effect on acute and chronic inflammation.