Our Oxymax and Metabolic Treadmill have long been the gold standard for measuring VO2 max in mice and rats. But telemetric measurements have always proved difficult on a treadmill. Static and motor electrical-noise have always interfered with the signal. But we have recently developed a special antenna for our treadmill that produces a clear signal for core body temperature and heart rate. Coupled with our Oxymax software, readings are recorded at 5-second intervals for heart rate, temperature, VO2/VCO2, RER, and energy expenditure. Also, all experiment parameters like treadmill speed and/or angle (requires the motorized incline option) are programmable from the software.