Research on "Three Supplements" to Aid Summer Workouts: Not a "Magic Pill"

Exercising in the hot season has become a more challenging topic than before. Morning jogs, outdoor club activities, summer marathons, and weight training in gyms where air conditioning is less effective. Just the high temperature can make your heart rate rise more easily, increase sweat, and decrease concentration, making "whether you can continue safely" a concern before performance.

In this context, a study introduced by The Independent is gaining attention. Researchers have identified three components—berberine, curcumin, and New Zealand blackcurrant—that may help alleviate the burden on the body of those exercising in hot environments. All are known as plant-derived ingredients and are available as supplements.

However, it should be emphasized first that this is not about "if you take this, you can exercise safely in the heat." The research indicates that these components may work as an aid against heat stress-related issues like body temperature rise, heart rate increase, inflammation, and gastrointestinal burden. Skipping basics like hydration, rest, shade, time adjustments, and acclimatizing to the heat, and relying solely on supplements is dangerous.

The study was introduced as content to be presented at the American Physiology Summit 2026 held in Minneapolis. Participants ran on a treadmill in a hot indoor environment after taking each supplement for a certain period. According to Outside, the environmental temperature was 93–98.6 degrees Fahrenheit, roughly 34–37 degrees Celsius. Participants ran for 60 minutes at an intensity of about 60–70% of their maximum oxygen uptake, and measurements were taken for body temperature, heart rate, blood and urine markers, and subjective exertion.

Of the three components studied, berberine is a type of alkaloid found in plants and has recently drawn attention for its relationship with metabolism, blood sugar, and weight management. In this study, it was reported that subjective exertion during exercise in the heat was reduced under the condition of taking 1.5 grams per day for one week.

Curcumin is the main component found in turmeric. It is often discussed in relation to its anti-inflammatory effects, and in this trial, improvements were observed in inflammation-related markers and gastrointestinal barrier function markers when 500 milligrams were taken daily for three days.

New Zealand blackcurrant is known as a berry material rich in anthocyanins. In this study, under the condition of taking 600 milligrams per day for one week, positive changes were observed in gastrointestinal barrier and inflammation-related markers, similar to curcumin.

Particularly interesting is the report that all three components suppressed the rise in body temperature during exercise. Furthermore, with berberine and curcumin, the increase in heart rate during exercise was suppressed by about 3–8 beats per minute. In hot environments, the body tries to dissipate heat by circulating blood to the skin, which can increase the burden on the heart. In this sense, the results related to heart rate and body temperature rise are intriguing data for athletes and those who want to continue outdoor exercise.

However, the important point here is not to conclude that "it worked." The researchers themselves are cautious, noting that the results do not prove that the supplements alone directly caused the outcomes. Outside's article also points out that experts describe it as "a small, controlled laboratory study that did not directly look at actual competition performance or heat illness prevention."

This difference is significant. In a laboratory, temperature, exercise intensity, time, and measurement items can be standardized. However, real summer exercise is more complex. Humidity, sunlight, wind presence, sleep deprivation, drinking the day before, diet, clothing, physical condition, medication, and acclimatization to heat—all these factors can easily negate the small benefits that might be gained from supplements.

Reactions on social media and forums also reflect this point well. Due to the article's recent release, large-scale reactions were limited, but related threads on Reddit show that interest in exercising or working in hot environments has been high for some time. Practical voices stand out, such as "hydration and electrolytes before supplements," "gradually getting used to the heat is important," "saunas or short-term heat acclimatization might help," and "use air conditioning, fans, and shade."

In martial arts and fitness threads, experienced individuals advise those struggling with training in hot gyms to focus on hydration, salt and electrolytes, rest, ventilation, light clothing, and not overexerting themselves. In other words, the sense on social media is quite realistic. While there is some expectation for new supplement research, many exercise enthusiasts believe that "ultimately, it's dangerous to neglect the basics."

On the other hand, there are already many people interested in components like berberine and curcumin in different contexts. Berberine is often discussed in relation to blood sugar and weight management, curcumin with inflammation and muscle soreness, and blackcurrant with blood flow and endurance performance. This study adds a new angle of "heat countermeasures" to these existing interests. Therefore, discussions may expand on social media about whether it can be used before summer competitions, if it serves as a heat countermeasure for runners, and how to combine it with electrolytes and caffeine.

However, there are other issues with supplements. The U.S. FDA does not approve supplements for safety and efficacy before sale like it does with drugs. The quality, ingredient amounts, and accuracy of labeling largely depend on the manufacturer's responsibility. The NIH also explains that while supplements may compensate for dietary deficiencies, they do not treat chronic diseases or replace basic health management.

There are also precautions regarding berberine. The U.S. NCCIH reports gastrointestinal symptoms such as nausea, abdominal pain, bloating, constipation, and diarrhea, and mentions the possibility of drug interactions. Especially those taking medication, pregnant or breastfeeding individuals, and those with chronic conditions should not take it on their own judgment.

Comments from the researchers in this study also suggest that supplements might be used for a short period before major competitions or events rather than being taken regularly. In other words, rather than taking them as a daily health habit, they should be considered in situations like "not having enough time to acclimate to the heat," "suddenly facing heat at a travel destination," or "wanting to consider support measures before a summer race," while consulting with a doctor or expert.

So how should the general public perceive this? The answer is simple. First, thoroughly implement the basics of heat countermeasures. Exercise during the coolest times possible. Avoid times with strong sunlight. Drink fluids frequently. Consider salt and electrolytes if sweating heavily. Stop if you experience dizziness, nausea, headaches, extreme fatigue, shortness of breath, or muscle cramps. Do not suddenly engage in high-intensity exercise on hot days; gradually acclimate your body.

With that foundation, it is natural for athletes and serious exercisers to pay attention to berberine, curcumin, and blackcurrant as one of the support measures. Particularly, the potential involvement of these components in multiple aspects of heat stress, such as body temperature rise, heart rate increase, gastrointestinal barriers, and inflammation, is intriguing. As the heat becomes more severe each year, the theme of sports nutrition is expanding beyond "running faster" and "building muscle" to include "continuing to move safely in the heat."

Still, supplements are not the main focus. The main focus is health management, adaptation to the environment, and the judgment not to overexert oneself. This study presents a new option for summer workouts. However, that option is not a "replacement for hydration" or a "substitute for choosing cooler times." It is not a shortcut to beating the heat but a small auxiliary wheel that might be used after maintaining the basics. This is the most realistic and safest way to interpret it.

Source URL

The Independent: Article reporting on the potential impact of berberine, curcumin, and blackcurrant on exercise in heat.
https://www.the-independent.com/life-style/health-and-families/supplements-workout-heat-fitness-summer-b2964670.html

Outside Online: Article confirming research content, test conditions, dosages of each supplement, and experts' cautious views.
https://www.outsideonline.com/health/nutrition/supplements-heat-training/

Newswise / American Physiological Society: Overview of research to be presented at the American Physiology Summit 2026. Presentation content on body temperature rise, heart rate, subjective burden, gastrointestinal barrier, and inflammation markers.
https://www.newswise.com/articles/dietary-supplements-could-protect-the-body-during-hot-weather-workouts

FDA: Basic information on supplement regulation in the U.S. Confirmation that the FDA does not approve supplements like drugs before sale.
https://www.fda.gov/food/information-consumers-using-dietary-supplements/questions-and-answers-dietary-supplements

NIH News in Health: General safety information explaining that while supplements may compensate for dietary deficiencies, they are not drugs and caution is needed regarding interactions and overdoses.
https://newsinhealth.nih.gov/2013/08/should-you-take-dietary-supplements

NCCIH: Overview of berberine, safety, gastrointestinal symptoms, and information on drug interactions.
https://www.nccih.nih.gov/health/berberine-and-weight-loss-what-you-need-to-know

CDC: Health measures for hot days. Information on staying cool, hydration, symptom awareness, and precautions for outdoor exercise.
https://www.cdc.gov/heat-health/about/index.html

Reddit / r/Biohackers: Examples of reactions on social media and forums regarding heat and humidity tolerance, electrolytes, saunas, and heat acclimatization.
https://www.reddit.com/r/Biohackers/comments/1fd8af3/supplements_that_desensitize_you_to_heat_and/

Reddit / r/NootropicsDepot: Examples of reactions emphasizing hydration, salt, cooling, and acclimatization to heat for work and exercise in hot environments.
https://www.reddit.com/r/NootropicsDepot/comments/13w6ole/what_supplements_can_help_aid_with_being_in_the/

Reddit / r/bjj: Practical reaction examples for training in hot gyms, focusing on hydration, electrolytes, rest, air conditioning, and fans.
https://www.reddit.com/r/bjj/comments/1egqndl/how_to_train_in_the_heat/

Reddit / r/Fitness: Experiences with acclimatization, hydration, salt, and cooling towels for training in hot gyms or outdoors.
https://www.reddit.com/r/Fitness/comments/hjbbmc/how_do_you_peeps_deal_with_the_extreme_heat_while/