Weekly Blog

July 2

We knew the "dog-days" would come; they always do. According to the Old Farmer's Almanac, this year they are right on time.  Even without our modern understanding of phenomena like the "heat dome" we are currently living under, astronomers from ancient Egypt and Greece knew that when Sirius (the dog star) rose—typically between July 3rd and August 11th—it would get hot. Unfortunately, this week could be a record breaker. Statistically speaking, this means injury risk, which tends to climb with the mercury, will also be higher than ideal. 

According to this study, which analyzed US industrial workplace data from 2023, the risk increases rapidly when temperatures exceed 85 degrees Fahrenheit. While not consistent across all sectors (utilities, for example, did not follow the pattern), the data showed that the odds of having an injury increased by an average of 3% when temperatures reached 90 degrees, 10% at 100 degrees, and 20% at 110 degrees - a classic "J"-shaped, exponential risk curve. 

The good news about highly predictable events like midsummer heat waves, however, is that we can prepare. We can build cardiac reserve by doing aerobic work 4-6 weeks in advance. We can start the acclimation process early by using controlled heat exposure 2-3 weeks prior, and we can have effective cooling strategies ready to deploy when the temperature spikes. The less good news is that not everyone chooses to. Therefore, a bit like releasing a procrastinator's guide to last-minute gift ideas on Christmas Eve, this week we are sharing a few evidence-based tips and tricks for managing the heat when we're in the thick of it. These tips are taken from three domains where excessive heat can have major consequences: the workplace, the elite playing field, and military operations.

(1) It's Personal: Perhaps the most important thing to remember is that since our movement system (cardiac & muscular tissues especially) both generates and dissipates heat, the baseline health of that system and the habits that impact it play a major role. Practically, this means individuals with lower fitness, higher age, extra body mass or habits that strain the system (tobacco, alcohol) struggle more in the heat than individuals without those risk factors. This May 2026 study, which examined indicators of cardiac workload in heavy agricultural work performed in the heat, showed that individuals with a higher baseline risk reached a cardiac strain threshold sooner and required more rest than those with a lower baseline risk profile.

(2) Not all cooling strategies are the same: While well-timed rest-breaks and efforts to lower body temperature are critical for performing in the heat, some work faster than others. This study compared various methods and found that although whole-body water immersion remains the gold-standard for rapidly lowering body temperature, limb immersion was a reasonably close second. Immersing the hands up to the elbows and the feet up to the knees outperformed sitting in air conditioning, which in turn outperformed resting without air conditioning. While limb immersion wouldn't be easy on a job site or at an athletic event, it might still be possible. If not, this 2024 review on heat mitigation tactics in construction and this small 2026 study on recreational soccer players showed that cooling vests show promise. However, this small study on factory workers showed that creating an "Oasis"—which consisted of 5 minutes of seated rest combined with hydration, iced towels, water dousing, and fanning—had a more potent effect than working in a cooling vest for an hour.
 

(3) There are signs: Like most risks we face, the body tells us when we are pushing toward our limits. The sooner we recognize the early signs in ourselves and those around us, the better chance we have to make changes before harm occurs. Excessive or unshakeable fatigue, brain fuzz and fog, gastrointestinal distress, rapid heart rate, muscle cramps or pain, and feeling (or looking) unsteady while walking are all signs that heat stress has progressed to strain. Since these typically occur before emergency signs like confusion or collapse, diligently monitoring those around us can prevent a situation from worsening. Time is essential; as discussed here, call for help, but begin cooling immediately. The first 30 minutes, sometimes called "the golden half hour," are critical.

Most of our clients' territory is under the heat dome. Whether on the jobsite or celebrating 250 years with family and friends at a backyard barbecue, managing and mitigating our risks can ensure we get through this first thermal test strong enough to take on the next one, which is almost definitely right around the corner.

On behalf of the entire team, Happy Independence Day.

Have a great weekend,

Mike E.