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April 10, 2024

The 5 Best Endurance Supplements, According to Research

Whether you’re training for your first long-distance race, planning weekly hikes with friends, or simply hoping to carry heavy bags of groceries for six blocks without huffing and puffing, building endurance is a priority.

Of course, you know there’s no skirting it.

The only way to improve your endurance is by exercising, and for longer.

But … is there anything else you could do to speed up the process? Uh, OK, this article’s title is a dead giveaway, so yes, you can turbocharge your efforts with endurance supplements.

We cover 5 of the best below.

What is endurance?

Before diving into the specific endurance supplements, let’s clarify what endurance is.

This knowledge will go a long way in helping you understand how endurance supplements keep you going and going (and going … alright, that’s enough; you get the point).

So, here goes.

Endurance is the ability to do something challenging for an extended period, generally at a lower-than-maximal intensity of effort level.

There are 2 types of endurance to know:

Cardiovascular endurance: The ability of your heart, lungs, and blood vessels to efficiently pump blood, which provides oxygen to working muscles for aerobic energy creation and removes waste products generated from energy production.
Muscular endurance: The ability of muscles to produce and maintain a particular level of force for a long duration. Influenced by cardiovascular endurance.

Endurance hinges on ATP creation

Alright. Now, let’s talk about energy, or more specifically, adenosine triphosphate (ATP) creation — because that’s what your muscles ultimately need to sustain a particular workload or pace during exercise.

Very briefly, your body relies on 3 energy systems to generate ATP.

#1: Phosphagen (ATP-PC) system

Most rapidly available source of energy.

Your muscles use stored creatine phosphate (CP) to produce ATP. This occurs without the need for oxygen.

However, as there’s only so much CP your muscles can store, the energy from the ATP-PC system lasts only about 10 seconds of maximal activity.

#2: Anaerobic glycolytic or lactic energy system

Here, glucose is broken down without oxygen to get ATP.

As it allows for more rapid production of ATP (note: glycolysis is ~100 times faster than the oxidative system), your body preferentially taps on it during activities that require bigger bursts of energy, lasting between 10 to 90 seconds.

#3: Oxidative system

The only energy pathway that requires oxygen.

Thanks to the presence of oxygen, your body can maximize the energy potential of a single glucose molecule — “extracting” ~32 molecules of ATP per 1 molecule of glucose.

In comparison, anaerobic glycolysis results in only 2 net ATP molecules per 1 molecule of glucose.

Due to its ability to generate tons of energy, your body favors this system for long-duration, relatively low-intensity cardiovascular activities.

All 3 energy systems are always active during exercise

FYI: this doesn’t mean that the oxidative system is the only energy system worth paying attention to when trying to build endurance.

Yes, your body will tap on a specific energy system preferentially during a particular type of exercise (e.g., the ATP-PC system during a short bout of sprints), but all 3 energy systems are always active during exercise.

And that’s why our list below includes a nice mix of endurance supplements that target different energy systems.

Evidence-based endurance supplements

#1: Caffeine

Caffeine is widely supported as an endurance-performance-enhancing supplement.

Its benefits have been seen across sports, from repeated sprinting to shot put to marathons. But how does the active ingredient in your morning cup of perk-me-up work?

There are 2 primary mechanisms at play:

Maintains oxygen levels in the blood: Remember the oxidative system? The more oxygen flowing through your bloodstream to your working muscles, the longer they can continue working.
Stimulates the central nervous system: Caffeine has been shown to reduce feelings of fatigue, lower perceived exertion, and even lower levels of perceived pain.

A few things to note about using caffeine as an endurance supplement:

Dose: The United States Food and Drug Administration (FDA) recommends consuming no more than 400 mg of caffeine daily.
Side effects: Caffeine may cause jitteriness, headaches, a fast heart rate, feelings of anxiety, and sleep disturbances. If you notice any adverse effects, you may wish to reduce your dosage or avoid caffeine altogether (don’t worry — there are plenty of other endurance supplements you could try!).

#2: Creatine

“Creatine” — doesn’t that look familiar? It should.

Because that’s what your body stores as creatine phosphate (CP), which is used in the phosphagen (ATP-PC) system as an immediate energy source.

Your body maintains its regular, unsupplemented creatine stores through:

The diet. Creatine is a naturally occurring non-protein amino acid compound found primarily in red meat (e.g., beef) and seafood (e.g., salmon).
Synthesizing it in the liver and kidneys.

The total creatine pool in the muscle averages about 54.4 mmol/lb of dry muscle mass for a 154 lb individual. However, the upper limit of creatine storage is higher, about 72.6 mmol/lb of dry muscle mass in most individuals.

So, by bridging the gap between your current and maximum creatine stores, creatine supplements extend the duration for which your body generates ATP through the phosphagen system.

The result: enhanced endurance.

#3: Beetroot juice

Beetroot juice has made quite a name for itself in the world of endurance supplements owing to the ample scientific evidence backing its endurance-enhancing benefits.

Its secret?

Beetroot juice is rich in nitrates, which get converted to nitric oxide when consumed. Research shows that nitric oxide could:

Open up your blood vessels, increasing blood flow and delivering more oxygen to working muscles
Act as a signaling molecule that ensures more blood flow to the muscles
Support optimal lung function for, once again, more oxygen to working muscles

#4: Carbohydrate supplements

Your body breaks carbohydrates down into glucose, which gets converted into ATP via both the anaerobic glycolytic and oxidative systems — in general, the more carbohydrates you consume, the longer your body can sustain the exercise.

In other words, if you want to work harder for longer, consider consuming carbohydrate-rich endurance supplements during prolonged bouts of exercise.

#5: Hydrogen water

Last but not least, hydrogen water.

Hydrogen water delivers molecular hydrogen, a tiny but mighty therapeutic antioxidant capable of diffusing into your mitochondria, the cell’s “powerhouse” where aerobic ATP production occurs, to support optimal energy production.

Of all the endurance supplements discussed in this article, you’re probably most intrigued by hydrogen water.

Like most adults, caffeine is probably already a mainstay in your life.

You get creatine through your diet. Beetroot juice sounds … interesting, but it's readily available in most grocery stores.

And carbohydrates — they’re a staple food.

So, hydrogen water. What’s that? Well, good news.

We have a whole series of articles meant to get you up to speed with this exciting supplement:

… and when you’re ready to unlock optimal health and wellness, check out Nutrionic™ H₂Energizer tablets here.