Triathletes love their stats. Whether it’s logging volume, time spent in target heart rates, or how much wattage they are putting out, we love to see how today’s performance stacks up against yesterday’s workout. There are plenty of benefits to taking a deep dive into the stats of your training sessions, not the least of which it gives you a clear representation of whether or not you are making progress.With plenty of raw data at our disposal we can see if the effort we are putting in on the bike, on the road, or in the pool are paying dividends. The sheer amount of data available does create an interesting problem—all of the information can begin to look like it all matters equally.Most triathletes I speak to will happily point to the mileage that they put in. But when pressed on how much of that volume is done at threshold, how much of it is specifically technique-based, or how many miles and meters are done at race pace, I usually get a bit of a blank stare.Take advantage of all the tracking tools available to you and start measuring the things that matter most to your training. Here are some suggestions.RPE (rate of perceived exertion). How difficult did your workout feel today? There will be some sessions where you are fresh and motivated and cranking out threshold reps feels border-line easy. Other days, you feel like you have a cement block tied to your waist, your legs feeling sluggish, and your mood profile tumbling accordingly. Tracking your RPE on a daily basis can give you a clear sense of when it’s time to back off and rest a little bit.Sleep. In the same vein, sleep is absolutely critical to your performance. The reality is that you can only train as hard as you are recovering. The stress that endurance athletes—as well as power and speed athletes—put on their bodies is very real. You don’t always feel it in terms of fatigue, but the blast of cortisol and hormone imbalance can take up to 48 hours to clear itself. Sleep helps to revitalize and refresh your body’s systems. Fortunately, most of the top triathlon and multisport watches on the market have sleep-tracking features that can spit out how much time you are spending at various stages of sleep. While sleep is usually the first thing that gets sacrificed when our schedule gets hectic, tracking it on a daily basis will remind you to make it a priority.Measure how often you are going race pace. Because I have a deep background in competitive swimming—qualified for Olympic Trials, national finalist—I get asked all of the time to help aspiring triathletes with their swim training. When I look over their swim workouts, there’s a very common theme—long, straight swimming with usually not-great technique. The first thing I suggest is for the athlete to set a goal time for the swim of their next race, and then break it into 100s (or 50s, if 100s are too hard). Technique falters less, average speed is higher, and you are acclimatizing your body to swim at the pace you want to race at. Tracking the number of meters you swam at the pool today is a far better indicator of how you are going to perform on race day compared to generic and border-line meaningless stats like overall volume.Triathletes are natural stat-nerds and journal-keepers. We are constantly looking at the clock, whether it's in the pool or on our watch, to see where we are at, how fast we are going, and how hard we are working. Use that inclination to stay on top of the things that have the greatest impact on your training, and by extension, the race you throw down when you step up to the starting line.