The word antler is derived from the Latin Anteoculae, meaning "in front of the eyes." Antlers are present in almost all members of the deer family Cervidae. The first documented evidence of deer velvet as a medicinal was found on a scroll recovered from a tomb in Hunan China dating back 2000 years. The use of antler dates back to the Han Dynasty 206 BC to 220 AD. A 16th century medical text, Pen Ts'ao Kang Mu, lists several antler preparations including pills, tinctures, and ointments. In traditional Chinese medicine, velvet antler has been used for over 2000 years as a tonic, to improve bone health, to nourish the blood, reduce swelling, and to treat impotence. Later research on deer antler dates back to the 1980s in Russia. Hundreds of articles have since been published including those documented by Chinese, Korean, and Japanese scientists.14, 15
A 2014 study published in Evidence Based Complimentary and Alternative Medicine tested whether or not deer antler extract would have an effect on fatigue in mice who were led to swim distances. The findings suggested that deer antler “might increase the muscle strength through the upregulation of genes responsible for muscle contraction and consequently exhibited the anti-fatigue effect in mice.” Deer antler seems to have a positive effect on genes involved in nine different signaling pathways that affect muscles, endurance and fatigue. These include GnRH signaling pathway and insulin signaling pathways, in addition to levels of troponins. (8) Deer antler may contribute to increases in muscle strength by increasing Tpm2 expression. This affects how muscles take up proteins and repair themselves. Other studies show some evidence that deer antler extract helps prevent muscle fatigue by activating the lactate dehydrogenase activities and reducing the levels of blood lactic acid and serum urea nitrogen.
A study by Chen found that deer antler velvet inhibits monoamine oxidase activity in the liver and brain tissues of aged mice. Monoamine-oxidase inhibitors prevent breakdown of monoamine neurotransmitters such as norepinephrine and serotonin. Antler apparently allows these vital neurotransmitters to be available longer to the brain structure, enhancing mood.
In a randomized, placebo controlled test in 2004, researchers at the University of Alberta, Canada, placed 18 males from the Edmonton Police Force into a 9 week strength training program. The results showed that deer antler velvet increased the strength and endurance of the subjects relative to the control group. The researchers found that use of deer antler velvet significantly increased blood plasma testosterone levels. 
A systemic review on human interventions[25] makes note of a study conducted on patients of osteoarthritis (Edelman et al. 2000; cannot be located online) which found improvements in joint pain symptoms relative to baseline in the Velvet Antler group and not placebo, although a lack of information on blinding and randomization precludes results that can be drawn from this study.