Exercise and Inflammation

"Inflammaging," late night workouts, seven days of cold plunge, your recommendations.

The Rundown

Exercise and Inflammation. Chronic low-grade inflammation typically increases throughout the body as we age and it’s connected to various health issues like heart disease, cancer and chronic pain. Scientists call it “inflammaging.”

Previous work has found that if you train for a few months, your baseline levels of inflammation decrease but they will go back up if you stop training. A new study published in Sports Medicine asks: If you train at a reasonable level and don't stop, can you avoid inflammaging altogether?

To find out, a team led by Inigo Perez-Castillo of Abbott Nutrition in Spain, looked at the results of 17 studies with 649 participants in order to compare lifelong masters athletes (people over age 35 who train and compete regularly in sport) with healthy, untrained people (both young and old). There isn’t a simple measure of inflammation so the researchers had to look at a lot of markers as a whole to get a sense of inflammation levels overall.

They found some patterns in the data. When compared with age-matched peers who don’t train, masters athletes had consistently lower levels of baseline inflammation. But if masters athletes were compared with people in the 20s who didn’t train, the young people had even lower levels.

The strongest results were in comparisons of C-reactive protein, which is associated with inflammation, and interleukin-10, which fights inflammation. Older athletes had less C-reactive and more interleukin-10. But for another marker, interleukin-6, the results were mixed: Training didn't lower baseline levels by a statistically significant margin but when the data was broken down by sport, endurance training had a significant benefit while strength training did not.

Night Moves. Past research has connected working out late to a bad night’s sleep if you exercise within two hours of going to bed. A new study from Monash University says it’s more like four hours.

Looking at international data from over 14,500 people who were monitored with a WHOOP strap that recorded exercise data, sleep and cardiovascular activity (adjusted to account for age, gender, weekday, season, overall fitness and how the participants slept the night before without evening exercise), the researchers found that previous estimates of exercise-related sleep disturbances might have underestimated the time you have to avoid a bad night’s rest by several hours.

While the team notes that their results don’t prove causation, they did find a consistent relationship across participants even when their data had been adjusted to factor in the variables mentioned above.

If evening exercise is what works for you, the researchers’ advice is to think about what you’re doing when. If your workout happens within four hours of when you go to sleep, maybe choose brief, low intensity activities to minimize sleep disruptions and allow the body to wind down. You could also track your biometrics overnight to see if sleep issues could be related to your evening workout and adjust the intensity accordingly.

Cold. Plunge. Repeat. Recent research from the Human and Environmental Physiology Research Unit (HEPRU) at the University of Ottawa discovered that seven consecutive days of cold water plunges significantly improved the body’s autophagic function, which is a critical cellular protective mechanism.

Autophagy is like the cleaning crew that finds all the junk in our cells (damaged proteins, worn-out pieces of cells, invading germs), collects it, breaks it down and then reuses whatever beneficial stuff is leftover. It’s a process that keeps cells healthy, helps protect against disease and plays a role when we exercise or fast by providing energy and nutrients.

For the study, ten healthy, physically active males with an average age of 23 submerged themselves in water that was 57.2 degrees Fahrenheit (14 degrees Celsius) for one hour a day, over seven consecutive days. The researchers monitored proteins in the volunteers’ blood to see how the plunges affected cellular stress responses, including autophagy.

Over the course of the week, the team found “marked changes at the cellular level,” a result they believe calls for further research into the effect of the seven-day plunge on aging and people with chronic diseases.

“We were amazed to see how quickly the body adapted,” said Kelli King, a postdoctoral fellow at HEPRU. “Cold exposure might help prevent diseases and potentially even slow down aging at a cellular level. It’s like a tune-up for your body’s microscopic machinery.”

Extra Point

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