The Pre-Workout vs. Coffee Test

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Today’s Health Upgrade

• The surprising electrolyte that improves sleep

• Cannabis and heart disease?

• The preworkout study

Instant Health Boost 
The Surprising Electrolyte That Improves Sleep

If you struggle to fall asleep or stay asleep, the first place to focus is your screen time or stress. But what you eat — and when — might also play a role

A new study suggests that your potassium intake could lead to a better night of rest. 

Researchers from Japan examined how the timing of sodium and potassium intake affects sleep. Each person completed detailed dietary records and took the Athens Insomnia Scale—a tool used to evaluate sleep quality and symptoms of insomnia.

The researchers weren't just looking at how much sodium or potassium people consumed. Instead, they were focused on when people consumed these electrolytes during the day—morning, afternoon, or evening—and whether that timing was linked to sleep problems.

The researchers expected sodium to influence sleep quality — but it didn’t.

However, those who consumed more total potassium, and particularly, those who had more potassium at night, experienced fewer sleep disturbances, a lower likelihood of insomnia, and higher sleep quality. 

We need more research to prove the relationship between potassium and sleep quality, but other studies have suggested a link between blood pressure and sleep. Your potassium levels influence blood pressure management. 

At night, decreases in blood pressure are associated with increases in sleep quality. So by influencing potassium intake overall and at night, you can help reduce your overall blood pressure, which can help solve sleep disturbances that disrupt quality rest. 

This doesn’t mean pumping up potassium too much. Instead, it’s being mindful of overall intake, and potentially adding high-potassium foods to the end of your day. Everyone thinks of bananas as a potassium powerhouse (and they are great!), but other foods are loaded with even more included white and sweet potatoes, watermelon, avocado, salmon, edamame, beans, lentils tomatoes, spinach, broccoli, zucchini, and Greek yogurt.

Health 
Does Cannabis Raise Heart Risk?

If you're one of the millions of Americans using cannabis for sleep, stress, or pain relief, new research might have you reconsidering your routine. 

Scientists found that cannabis use was linked to a higher risk of heart attack, stroke, and even cardiovascular death — but a few details mean you should not jump to conclusions.

Researchers reviewed 24 studies published between 2016 and 2023.. These studies tracked people who used cannabis and measured rates of major cardiovascular problems—such as heart attack (acute coronary syndrome), stroke, and cardiovascular death.

Cannabis users showed a 29 percent higher risk of heart attack, 20 percent higher risk of stroke, and more than double the risk of cardiovascular death compared to non-users.

The stroke risk increase was particularly consistent across different study designs, while the cardiovascular death risk—though based on fewer studies—showed the most dramatic increase at 110 percent.

THC can increase heart rate, blood pressure, and the heart's oxygen demand while potentially disrupting normal heart rhythms. Cannabis may also affect blood clotting and inflammation—both key players in heart attacks and strokes. Think of it like putting extra stress on your cardiovascular system when it's trying to function normally. Over time, these effects could increase strain on the cardiovascular system, especially in people with underlying health issues.

The authors are careful to note that more research is needed, especially since most studies were observational and couldn’t prove cause and effect. 

If you currently use cannabis and have any cardiovascular risk factors—high blood pressure, diabetes, family history of heart disease, or if you're over 45—schedule a conversation with your healthcare provider. 

This research does not mean cannabis will definitely cause heart problems for everyone, but it does suggest the risks might be higher than previously thought—especially for people who already have cardiovascular vulnerabilities.

Friends Don’t Let Friends 
Waste Money On Pre-Workout (If They Drink Coffee)

Walk into any gym, and you’ll see shaker bottles lined with neon-colored powders promising more energy, strength, and muscle. But, there’s a little secret many of those expensive products don’t want you to know:

If you’re already a coffee drinker, new research suggests expensive pre-workouts might not add much beyond what’s in your mug.

Researchers tested whether a pre-workout mix (vegan protein, amino acids, and 400 mg caffeine) was more effective than about 60 grams of carbs before a workout. Over six weeks, both groups trained three times per week. Everyone made progress: fat mass dropped by about 1 kg, muscle increased by nearly 1 kg, and strength, power, and endurance all improved. 

Some are saying, “pre-workout does nothing” — but that’s not exactly the full story. Because a small study detail shares what really happened.

Most of the participants were already caffeine regulars, drinking at least three cups of coffee or tea per day. 

That meant the pre-workout group was taking in closer to 500–700 mg total caffeine on training days—more than double the carb group—yet still didn’t see extra benefits. 

In other words, for people who already consume caffeine daily, pre-workout supplements didn’t lead to better muscle or fat loss results compared to simple carbs before training.

The researchers suggest caffeine has a limit where more doesn’t necessarily improve performance.

Caffeine can sharpen focus, reduce perceived effort, and boost performance—but only up to a point. Once you hit that amount, combining coffee plus a pre-workout doesn’t magically accelerate results.

If you’re a regular coffee or tea drinker, you might not get any extra benefit by spending big on pre-workouts. About two or three cups of coffee (around 200 mg caffeine) and some quick-digesting carbs before training can give you the same edge. 

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Publisher: Arnold Schwarzenegger​

Editors-in-chief: Adam Bornstein and Daniel Ketchell