Over the course of your life, your heart has the ability to beat over 3 billion times, making it the hardest-working muscle in your body. Each one of those beats involves the coordination of a complex system of muscles, veins and arteries in charge of oxygenating your entire body.
So, how do you make sure that this important organ is healthy and happy? A simple way to gain insight into your heart health is by tracking your resting heart rate, or the rate at which your heart beats when you’re not active (like early in the morning, before you’re up and about). A lower resting heart rate usually indicates that the heart is being more efficient, requiring fewer beats per minute to pump the same amount of blood.
Some of your resting heart rate arises by virtue of your gender, age, height or weight, and changes slowly over time. Small day-to-day variations, however, can result from many different kinds of behaviors, from how much sleep you got last night to how hydrated you are. Our previous heart rate blog post summarizes these factors, which also include diet, exercise, and stress.
Since the release of our UP3 fitness tracker, tens of thousands of users have been consistently tracking their resting heart rate with the band. To give you a better idea on how you can improve your heart health, we took a look to see how heart rate changes based on the anonymized data of UP users.
Among UP users, males have an average resting heart rate that is 3.4 beats lower than females. Users with lower BMIs have a lower resting heart rate.
HIGHER BMI, HIGHER RESTING HEART RATE
When comparing activity levels, people that on average take more steps have lower resting heart rates.
MORE ACTIVE USERS HAVE LOWER HEART RATES
In addition, people’s resting heart rates vary along with their primary activity type.
RUNNERS AND BIKERS HAVE THE LOWEST RESTING HEART RATES
There are many short-term behaviors (from how much you slept last night to how much coffee you consumed the day before) that can slightly affect your resting heart rate the next morning. We identified some of the day-to-day factors that affected UP users’ resting heart rates. The most important factor was bedtime; going to bed later than usual is correlated with a higher resting heart rate the next morning. In fact, even when people sleep more on the weekends, they tend to go to bed later and experience higher heart rates.
LATER BEDTIME, HIGHER HEART RATE
Note: this graph looks at males age 20-35 to minimize the confounding effects of gender/age.
There are lots of possible explanations for later bedtimes correlating with higher resting heart rates. For example, people going to bed later may be amped up on caffeine or missing out on restful sleep. The ‘weekend spike’ may also be linked to alcohol consumption on weekends causing dehydration. All these factors are known to disturb heart rate.
So, if you’re planning to stay out late, make a heartfelt effort to stay hydrated, limit caffeine intake, and get into bed at a reasonable hour. It may not sound like the “party spirit”, but your body will celebrate the little changes over time with a lower resting heart rate, more sleep, and an overall improvement on your health. And that’s something to really celebrate.
Technical Notes: This study was based on tens of thousands of UP3 wearers who have regularly used UP3 by Jawbone over the past 2 months to track their sleep, steps, and resting heart rate. We analyzed hundreds of thousands of days of steps/nights of sleep. For the workout analysis, each user was only classified as a “runner” (or other) if running was that user’s top-logged workout and it made up greater than 40% of all that user’s workouts. For the bedtime analysis, a random forest regression model was used to determine that bedtime was the most influential feature of those considered. All data is anonymized and presented in aggregate.