Mood, Hourly Sprints & Real Time Zones

This week we've been thinking a lot about time and how to make the most of it.

Podcast

The Complicated Relationship Between Sleep and Mood. Podcast with Dr. Jennifer Goldschmied

Dan got to speak with Jennifer Goldschmied. Jennifer has a Ph.D. in Clinical Psychology from the University of Michigan, and is currently faculty at the University of Pennsylvania.

Her research explores how altering aspects of sleep can produce changes in mood and emotional regulation, particularly in those with major depression. Jennifer’s work has led her to investigate a long-recognized but poorly understood clinical paradox: Certain individuals actually experience mood improvement in response to sleep loss. That's right - total sleep deprivation has been shown to have antidepressant effects. Remarkably, an estimated 40-60% of people with major depression may experience significant improvements in symptoms.

These benefits dissipate once the patient’s sleep is restored, which is probably why interest in this as a therapy has lagged. But Jennifer and her colleagues are starting to figure out why precisely sleep deprivation seems to improve mood, and which individuals might stand to benefit from sleep manipulation that may eventually lead to new treatments for depression and other mental disorders.

Research Highlights

Very short sprint intervals throughout the day can prevent impairment in postprandial fat metabolism associated with inactivity. Four men and four women participated in two trials. These interventions consisted of an 8 hour period of sitting (representing a typical workday for most knowledge workers), or a trial with equal sitting time interrupted with five 4-second sprints using an inertial load ergometer every hour. Compared with the sedentary group, the sprint group displayed a 31% decrease in plasma triglyceride incremental AUC and a 43% increase in whole body fat oxidation. If you don't have the space to sprint outside, running on the spot works a treat and if you're worried what other people think, just switch off the camera on Zoom.

Consumption of ultra-processed food is linked to greater adiposity in the UK population. Researchers studied data from 6143 participants sampled by the UK National Diet and Nutrition Survey to determine associations between dietary contribution of ultra-processed foods and various measures of adiposity. In multivariable analyses, the highest consumption of ultra-processed food was associated with 90% higher odds for being obese, compared to the lowest consumption. A similar dose-response relationship was observed in both sexes, with a 10% increase in the consumption of ultra-processed foods being associated with a 18% increase in the prevalence of obesity in men and a 17% increase in women.

Microwave cooking increases levels of sulforaphane in broccoli. Sulforaphane has been associated with various health benefits and may beneficially affect cancer, heart disease, diabetes, and digestion. Researchers took broccoli samples and exposed them to either conventional low-temperature cooking (with water in a covered pot), or immersed in water and cooked in a microwave oven at various settings and power levels. After cooking, samples were freeze-dried and analyzed for bioactive compounds. Both microwave treatment and mild heating increased glucoraphanin and sulforaphane levels compared to raw samples, but the microwave cooking produced the best results. Compared to conventional cooking, the microwave heating increased GLR and SFR yield by about 80% at 50 and 60°C. Microwave power level also influenced sulforaphane contents. High‐power microwave (950 W) produced over 40% more sulforaphane than low‐power microwave treatment (475 W).

Adding a layer of women's tights to homemade masks may significantly boost its ability to filter out small particles. With a restrictions on movement being slowly lifted there has been much discussion on the use of masks. Early on the pandemic Lex Fridman from MIT shared this research which demonstrated air flow from a person breathing, talking, and coughing, with and without face a mask. Since then, researchers at Northeastern University collected ten homemade fabric masks with different designs, as well as three commercially produced surgical masks. They used an instrument called a PortaCount - which is normally used to fit-test the filtering capabilities of medical-grade masks like N95 respirators - to measure the ability to block out particles ranging from 20-1000 nanometers. The device measured the number of particles immediately outside and inside each mask while someone was wearing it. Then, the researchers added a nylon stocking overlayer made by cutting a ring of material, about 8 to 10 inches top to bottom, from one leg on a pair of pantyhose. When worn alone, the homemade masks' abilities to filter varied widely, with some blocking fewer than 30% of particles. But adding the pantyhose layer boosted all the masks' performance by anywhere from 15% to 50%.

For knowledge workers, distance suddenly matters less than it used to. Our friend and Head of Innovation Design at the MIT Collective Intelligence Design Lab, Gianni Giacomelli took population and GDP data, approximately broke them down by time zone, and estimated when they were available in order to plot the available “global brain’s processing power” against the cycle of a 24 hour day. The peak of concurrent resources being "online" falls between 7 a.m. and 6 p.m. GMT using GDP as a proxy for highly skilled knowledge workers, and a little earlier if we use general population. This is great news if you're physically based close to GMT and working with global teams. We'll dig into this a bit more deeply another time.

What we've been listening to

Josh Turknett: How to Protect Your Brain from Decline.Via Nourish Balance Thrive Podcast.

Eric Trexler: Antioxidants, Oxidative Stress, & Exercise Adaptations. Sigma Nutrition Radio.

Mark Blagrove and Julia Lockheart: Do Dreams Have a Social Function? COVID-19 Special Report. Via Sleep Junkies.

Course of the week

An Introduction to Your Body’s Clock

In humanOS, we have built up a vast library of courses that address assorted topics in personal health (all fully available to anyone with a humanOS Pro account). When we talked to Gianni earlier this week it prompted us to join a few dots and in the spirit of the human centric design approach we love we asked the question "How might we better align our individual circadian rhythm to those of our global team mates to be more effective as well as healthy?" We'll dig into that a bit more next week but for now you can find out the fundamentals in this course from our Circadian Program, developed by Greg Potter PhD.

Our bodies, like those of other organisms, follow a (roughly) 24 hour physiological pattern. But why did we evolve this system? And how are these rhythms governed within the body?

In this course, Greg describes characteristics of biological rhythms, how circadian rhythms are regulated in our bodies, and the types of environmental signals that can entrain (or derail) our internal clocks. When you fully appreciate how ubiquitous and vital these biological rhythms are for pretty much all living things (including us), it becomes clear why keeping them in alignment is worthwhile for maintaining your health and performance, both over the short and the long term.

As always, we want our work to be accessible to everyone so if the small cost of a subscription to our Pro accounts is an issue just drop me a line and we will sort something out.