There are several reasons why you might have consistently low HRV scores. Age3, pre-existing medical conditions, lifestyle factors, nutrition, overtraining, and stress management all impact heart rate variability.
“Population-based studies tend to find that HRV decreases as we age. This may be part of the natural aging process, and it is likely representative of the typical decline in cardiovascular fitness4 we see in the aging population,” explains Reed.
Evidence also suggests that people with cardiovascular and metabolic diseases tend to have lower HRV than those without chronic conditions. "Some good news for people who fall into this category, though, is that when [they] participated in exercise training programs, they saw improvements in HRV5 (and in outcomes related to CVD)," Reed adds.
Gabrielle Manto, D.C, a prenatal and pediatric chiropractor, collects HRV data from all her patients, including infants, active adults, and people with rare genetic disorders. She is currently collecting data on HRV trends during the perinatal period (around the time of conception, pregnancy, and postpartum) and during each phase of the menstrual cycle.
“In our office, we rescan HRV every 12 adjustments or sometimes pre- and post-adjustments to measure change,” says Manto. “What we are finding is that after conception, HRV will trend down, and then around six weeks postnatally, HRV will trend up.”
In addition to longer-term factors, there are a few reasons your HRV could dip from day to day, including dehydration6, illness7, poor sleep8, and even flying9!
For example, this past week, Deehan had a few nights of poor, interrupted sleep, followed by a red-eye to a time zone six hours ahead and long days at work. She noticed her HRV dropped significantly for six days.
According to user data from WHOOP, when members report consuming alcohol, their HRV drops by an average of 22 milliseconds the next day. Their research has also discovered that the lingering effects of alcohol in your system may continue to suppress your heart rate variability for four to five days.
A small-scale randomized controlled trial10 in 2010 found that drinking two servings of red wine or alcohol can decrease total HRV by 28 to 33%, with the effects lasting days.
