Air Supply

In this week's Rundown, it's fast water filtration, thinking twice about indoor workouts, and the weight loss benefits of resistance training.

The Rundown

Hiking Hydration. On a hike, filtering water can often be time consuming. The Platypus QuickDraw Microfilter System is designed to make it quick and easy. The compact, 3.3 ounce kit has a one-liter soft-sided reservoir usefully labeled “dirty,” and a hollow fiber filter that sits inside a durable ABS-plastic casing. To collect clean water, you fill the reservoir, screw the filter onto the top and squeeze. The 0.2 micron pores remove bacteria and protozoa but not viruses, which are only removed by purifiers.

Air Supply. Many of us are back in the gym but according to a new study focused on respiration and exercise, the amount of microscopic aerosol particles that the person next to you is breathing out may make you think twice about an indoor workout, particularly if you’re concerned about exposing yourself to Covid or other respiratory viruses.

To measure the number of aerosol particles that 16 people exhaled during a workout, the scientists used a stationary bike and rider inside an airtight tent. The riders wore silicone masks that sent the air from their exhaled breaths through tubes to a machine that counted each particle. For comparison, the participants’ aerosol emissions were first measured as they sat still.

The researchers expected aerosol output to increase as the exercisers’ intensity rose but the extent of the increase was surprising, according to a senior author of the study. As the riders’ workouts became noticeably harder (think interval intensity), the number of particles per minute increased dramatically. At rest, the men and women breathed out about 500 particles per minute. At the hardest part of their workout, the number rose to more than 76,000 particles per minute on average.

Experts on airborne transmission of viruses say that open windows, fans, air conditioning units that draw air from the outside and air filters are all mitigating factors. Staying away from other exercisers as much as you can helps, and if you take a class, at least 15 minutes and preferably 30 minutes, is best between sessions to allow the air to clear.

Rethinking Aerobics. The typical conversation around exercise and weight loss focuses on aerobic exercise but a recent paper shows that with the right diet, resistance training (such as body-weight exercises or using weights) can have similar effects when it comes to burning fat.

Researchers at Australia’s Edith Cowan University conducted a meta-analysis on the effects of resistance-based exercise programs on body fat in obese and overweight subjects across their lifespan. The data came from 114 trials, which enabled the team to compare how aerobic training and resistance training effected body fat percentage, fat distribution, and lean muscle mass, when combined with a healthy diet.

The team found that resistance training offered similar benefits for weight loss to aerobic training, with the right diet. Lead researcher Pedro Lopez says, “Usually when we talk about obesity, body composition or weight loss, we only hear about aerobic exercise. This paper shows we can use resistance training and achieve meaningful effects with a diet based on caloric reduction.”

Replay

This week’s vintage moment in fitness culture is brought to you by 2013 viral hit, Prancercise, which mimics a horse’s gait and is “induced by elation.”