The BSXInsight by BSX Athletics is revolutionizing how athletes train and improve. Using an optical sensor, the BSXInsight is worn on your calf with a compression sleeve to gather information on local metabolic activity and provide data on your lactate threshold. The BSXInsight can also be paired with various ANT devices to extend its fitness tracking to heart rate and cycling power. The BSXInsight can be purchased in 3 different packages; the running edition for $299.99, the cycling edition for $369.99, and the multisport edition for $419.99.