Recovery tracking that actually tells you what to do

What is Body Charge?

Body Charge is Cora's daily recovery score. It is a single number between 0 and 100 that represents how recovered your body is and how ready you are to take on physical stress. Think of it as your body's battery level for the day.

Most fitness apps give you raw data and leave you to figure out what it means. You see your HRV number, your sleep stages, your resting heart rate, but you have to piece together the full picture yourself. Body Charge does that synthesis for you. It weighs the inputs that matter, accounts for trends over time, and gives you one clear score that answers the question: "How hard should I train today?"

A Body Charge of 80 or above means your body is well-recovered and ready for high-intensity work. Scores in the 50 to 79 range suggest moderate training is appropriate. Below 50, Cora will recommend lighter activity or full rest to help your body catch up. These are not arbitrary thresholds. They are calibrated to your personal baseline and adapt as Cora learns your patterns.

How recovery tracking works in Cora

Every morning, Cora pulls the latest data from your wearable device. It collects three primary inputs: your sleep data (duration, stages, and disturbances), your heart rate variability (HRV), and your resting heart rate. These three signals are the most reliable, research-backed indicators of physical recovery available from consumer wearables.

Cora does not just look at last night's data in isolation. It compares your numbers against your personal rolling baseline. A resting heart rate of 55 bpm might be perfectly normal for one person but elevated for another. By tracking your individual trends over weeks and months, Cora builds a model of what "normal" looks like for you and detects meaningful deviations.

The result is a Body Charge score that reflects your actual physiological state, not a generic estimate. It accounts for training load from previous days, sleep quality trends, and autonomic nervous system balance as measured through HRV. All of this happens automatically in the background. You just wake up, check your score, and know where you stand.

HRV explained simply

Heart rate variability, or HRV, measures the variation in time between consecutive heartbeats. Contrary to what most people assume, a healthy heart does not beat like a metronome. There are tiny, natural fluctuations between each beat, and the size of those fluctuations tells you a lot about your body's recovery state.

Higher HRV generally indicates that your body is in a well-recovered, parasympathetic (rest-and-digest) state. Your nervous system has the capacity to handle stress, which means your body is ready for training. Lower HRV suggests your body is still working to recover from previous stress, whether that was a hard workout, poor sleep, illness, or psychological stress.

The key insight is that HRV is most useful as a trend, not as a single data point. Your HRV will naturally fluctuate from day to day. What matters is whether your HRV is trending up, trending down, or holding steady relative to your personal baseline. Cora tracks this trend for you and factors it into your daily Body Charge score, so you do not need to interpret raw HRV numbers yourself.

Sleep tracking that connects to your training

Sleep is the single most important factor in physical recovery. You can have a perfect training program and a dialed-in nutrition plan, but if your sleep is consistently poor, your progress will stall. Cora takes sleep data seriously and gives it significant weight in the Body Charge calculation.

Using data from your wearable, Cora tracks your total sleep duration, the time you spent in each sleep stage (deep, REM, light, and awake), and the number of disturbances during the night. It does not just show you a chart and leave you guessing. Cora tells you how your sleep last night compares to your recent average and whether it was sufficient to support recovery from your training load.

Over time, Cora identifies patterns in your sleep data. Maybe your deep sleep drops after evening workouts. Maybe your sleep efficiency improves when you go to bed at a consistent time. These insights surface in your daily coaching feed, helping you make small adjustments that compound into better recovery and better results.

How Cora uses recovery data to adjust your training

This is where recovery tracking becomes more than just a number on a screen. Most recovery apps show you a score and then leave you to decide what to do with it. Cora closes that loop. Your Body Charge score directly influences the workout plan that Cora generates for you each day.

When your Body Charge is high, Cora knows your body can handle more. It will program higher-intensity sessions, increase training volume, or schedule a particularly demanding workout that it has been waiting for the right day to assign. When your Body Charge is low, Cora automatically scales back. It might reduce the number of working sets, lower the prescribed intensity, swap in lighter exercise variations, or recommend an active recovery session instead.

This adaptive approach helps you avoid two common training pitfalls. The first is overtraining: pushing through hard sessions when your body is not recovered, which leads to fatigue, injury, and burnout. The second is undertraining: taking it easy on days when your body is fully charged and could benefit from a challenging workout. Cora keeps you in the productive sweet spot between the two.

Why recovery matters for consistency

The biggest predictor of fitness progress is not the intensity of any single workout. It is consistency over weeks, months, and years. And the number one thing that kills consistency is pushing too hard, getting hurt or burned out, and needing to take extended time off.

Recovery tracking helps you stay consistent by keeping your training sustainable. When you train according to your body's actual readiness rather than a fixed schedule, you naturally avoid the boom-and-bust cycle that derails so many training plans. You train hard on the days when your body is ready and back off on the days when it needs rest.

The result is a more even distribution of training stress, fewer forced rest days due to fatigue or injury, and a stronger long-term trajectory of improvement. Whether your goal is building muscle, improving endurance, or losing body fat, recovery-aware training gets you there faster by helping you avoid the setbacks that slow most people down.

Frequently Asked Questions