How do you know if you are training too hard? Your Apple Watch can help you. Your Heart Rate Variability (HRV) is an indicator, the higher the variance between your heartbeats, the more ready you are to train. Your Apple Watch automatically measures your HRV periodically. That means just by wearing your watch as much as you can, you can get this metric for free. You can view your HRV in the Health app on iPhone, or use @tenniskeeperapp HRV graph to help you get insights on your HRV variation over a week, 1, 3 or 6 months period. . . . . . . #newzealandtennis #tenisbrasil #tennischampionsslovakia #tennisswiss #greecetennis #supporttheswiss #tennisbarcelona #tennistraining #tenniskeeper #heartratevariability #tennisportugal #tennisplayer #tennislove #tennislife #tennispro #heartratetraining #applewatchfitness #applewatchfans #applewatchsport #activityapp #tennisday #tennistrainer #tenniscoach #tennismatch #tennistournament #tennisfit #tennisdrills #tennisfun #ilovetennis (at Amsterdam, Netherlands) https://www.instagram.com/p/CBa8b1xgpRc/?igshid=5sx953evox1e