This is the Most Important Apple Watch Metric for Entrepreneurs You should use the data from your Apple Watch to perform at your peak.

The grind. The hackathon. The "We don't sleep, we pass out." The Slacks at 2 a.m. The "always-on" expectation. We may do this precisely because we often don't have many physical demands on our bodies. Therefore, we crave a physical challenge — and we turn our mind work into body work.

But thinking of business performance success in terms of actual physicality can be dangerous. In particular, as we hit our late thirties and forties, we want to see how much we can do before breaking. Long term, this is a recipe for burnout.

The data from our Apple Watches and wearables can be a goldmine for personal development and help improve our long-term business performance. Looking back on the data it collects is fascinating, especially the heart rate data.

The metric most important for entrepreneurs to watch and improve is HRV (Heart Rate Variability.) HRV is the variance of time between the beats of your heart. Our hearts are not metronomes, but rather should work like a finely tuned sports car engine, revving up and down responsively. Generally, the more variance, the better, as we want our hearts to be agile and adaptive to our environment.

It essentially measures your heart's readiness to perform and react to the demands we place on our body. Think of your average resting heart rate as an indicator of cardiovascular health. Think of HRV as your body's ability to adapt to change rapidly. What is better for entrepreneurs than the ability to rapidly adapt and change according to conditions and workload?

HRV is a crucial metric to track with your Apple Watch or wearable device because by improving the metric, we strengthen our ability to perform and execute. We improve the HRV metric by not pushing ourselves to the limit physically, but rather by balancing our lives with the proper amount of exercise, rest and stress mitigation. Here are four specific ways you can improve your HRV — and reap the benefits of a healthier lifestyle.

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Smart training

It's always in the last quarter of a run that I do my best thinking about my business. But on the flip side, too much exercise can lead to exhaustion. Periods of intense exercise will actually lower your HRV, giving the indication that we need a break and rest period. Allow yourself this rest to increase your ability to push yourself later.

Quality sleep

Sleep is an essential factor in HRV. Specifically, this factor is most correlated with the quality and consistency of your sleep. It's easy to go from our laptops during the day to our phones before bed, but this can disrupt our sleep schedule. Take care of yourself as you would a little kid, and go for a regular bedtime.

Related: How a Better Night's Sleep Can Help Entrepreneurs Stay Calm and Focused at Work

Water, water, water

The millennials may be on to something with their ridiculously overpriced and massive water bottles. Proper hydration has a strong effect on HRV. The doctors all tell us to drink water, and as much as possible, let's knock this one off the list.

Watch the alcohol

Alcohol can be a quick fix to stress, but it's a shortcut to nowhere. Alcohol has been shown to negatively affect HRV for up to four days after drinking! If it's affecting your heart's ability to react to change, what else is it affecting? This one is tied to all the others, as alcohol affects training, sleep and hydration.

For busy entrepreneurs, being able to push yourself is undoubtedly an excellent trait to have. But how do you perform at your best for the extended period needed to build a great business? HRV is a great metric to track and improve. In doing so, you'll set yourself up for great long-term performances and build your capacity for peak execution.

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