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Today’s Health Upgrade

• Deep dive: baking soda is an effective sports supplement

• Is running really bad for your knees?

• Temptation and discipline

Deep Dive
Does Baking Soda Improve Performance?

Baking soda has something most performance supplements would love: enough evidence to earn an official position stand. It also has a side-effect problem that can make even the best boost not worth it.

Baking soda can boost performance during hard efforts lasting roughly 30 seconds to 12 minutes. But it can also cause GI issues that may offset the real benefits.

The evidence is consistent, and the gains are real, but it won’t make you superhuman. According to the International Society of Sports Nutrition position stand, baking soda improves performance in muscular endurance work, combat sports, and high-intensity cycling, running, swimming, and rowing. Think 400- to 1,500-meter runs, 2,000-meter rows, combat-sport rounds, or high-rep sets taken close to failure.

An umbrella review of eight meta-analyses found small improvements in events lasting about 45 seconds to eight minutes, muscular endurance tests, and the Yo-Yo intermittent running test.

But that doesn’t mean it works for every fitness goal. The study found no significant benefit for maximal strength or repeated-sprint ability. 

Baking soda helps buffer one of the things that makes your muscles tire.

During hard exercise, acidity builds faster than your muscles can clear it. Bicarbonate is one of the body’s primary buffers. A large dose of baking soda raises blood bicarbonate levels, which can help move acid out of working muscle and let you maintain a difficult pace a little longer.

The best-supported dose is 0.3 grams per kilogram of body weight, taken 60 to 180 minutes before exercise. 

Higher single doses don’t appear to add benefit, but they do increase side effects.

But as we mentioned, fighting fatigue can come with side effects you’d probably prefer to avoid when working out.

The most immediate problem is your gut. In one blinded crossover trial, participants drank 0.3 g/kg dissolved in water all at once, and 10 of 11 developed diarrhea. Nearly two-thirds reported bloating, and 45 percent experienced nausea. That’s close to a worst-case setup (one big dose, no food), and reactions vary a lot from person to person.

A 2026 review of 101 investigations concluded that stomach problems are tied to the dose, timing, and the form you take it in. Spreading the dose over several hours, using enteric-coated capsules, or following a multi-day protocol might help, although the research isn’t strong enough to say which strategy works best.

If you want to see whether baking soda works for you without the downsides, start with 0.2 g/kg with a carbohydrate-rich meal and plenty of water.

Test it on a normal training day, and take it 60 to 180 minutes before the workout. If that goes well, you can move toward 0.3 g/kg or stick with the lower dose if it makes a difference.

Don’t try it for the first time before a race or competition. Skip it for maximal-strength work, easy cardio, and long steady endurance sessions. And don’t treat it like a daily supplement. Use it selectively for the sessions or events where a small improvement could matter.

And a word to the wise: a 0.3 g/kg dose for a 155-pound person contains about 5,700 mg of sodium, more than double the recommended daily limit. If you have high blood pressure, heart failure, kidney disease, or have been told to limit sodium, get medical clearance before experimenting with it.

Reader Question
Does Running Destroy Your Knees?

The Short answer: Regular running does not appear to wear down healthy knees. 

In a meta-analysis of about 115,000 people, recreational runners were no more likely than sedentary non-runners to have hip or knee arthritis. 

And a separate assessment of nearly 4,000 Chicago Marathon runners reached a similar conclusion. Years of running, weekly mileage, and number of completed marathons weren’t linked to arthritis. 

However, age, body weight, family history, and previous knee injuries or surgery were the strongest associations for knee issues.

These studies are observational, so they can’t prove running protects your knees. But they don’t support the idea that regular running wears them out.

The “wear and tear” argument treats cartilage like tire tread. Cartilage is living tissue that responds to load. Running produces peak forces about three times higher than walking, but each stride covers more ground and spends less time on the ground, which offsets some of that force. 

The debunked theory may reflect the resilience of the human body. Researchers also think cartilage adapts to regular running, much as muscle and bone do.

Trials of knee-loading exercise suggest it doesn’t harm cartilage, even in people who have or are at risk of knee arthritis. MRI studies show that cartilage compresses slightly during a run, but the change appears temporary.

That doesn’t mean runners never have knee trouble. 

The knee is the most common site of running injuries, usually from overuse problems like runner’s knee rather than arthritis. 

These injuries can linger when ignored, and knee problems are more the result of poor form, poor programming, and then ignoring the issues and trying to power through when your body says you need to make a change. 

Running won’t necessarily hurt your knees, but once you have a knee injury, the risk increases. 

In the marathon survey, prior knee or hip surgery was associated with nearly six times the odds of arthritis.

Mindset
The Most Disciplined People Resist Less

A routine that makes you fight temptation all day takes a lot of work to maintain. The most self-controlled people might do less of that work than you’d expect.

Research suggests that people who seem most disciplined face fewer temptations and fewer conflicts with their goals.

Researchers gave adults smartphones that buzzed at random times, seven times a day, for a week. Each time, participants reported whether they wanted something right then, whether that desire clashed with one of their goals, and whether they tried to resist it.

Some kind of desire showed up about half the time. People who rated themselves higher in self-control reported somewhat weaker desires and less conflict with their goals.

After accounting for how conflicted people felt, those who scored well above average in self-control were estimated to resist about 35 percent of the time, compared with 42 percent for those well below average.

They weren’t any better at resisting when they tried. They just had to try less often.

That distinction matters if your plan for getting healthier depends on constantly telling yourself no.

In another study, how much people relied on effortful self-control didn’t predict how much progress they reported on their goals by the end of the semester. Facing fewer temptations did.

And a review of 102 studies found that, in studies using the most common self-control questionnaire, self-control was more than twice as strongly linked to automatic, habitual behaviors as to behaviors that take conscious effort.

Sleep deserves some attention here. Across 61 studies, worse sleep was linked to weaker self-control, including changes within the same person over time.

It’s why we’re big fans of better beds and better pillows. Our readers call them game-changers because they can feel the difference once sleep improves.

We don’t know whether disciplined people arrange their lives to make healthy choices easier or simply have easier circumstances.

Still, making a routine easier to follow is a practical place to start if you want to build consistent, automatic behaviors that become habits.

If this doesn’t come naturally, pick one thing you repeatedly struggle with, and change what happens before you have to make the choice. If your phone keeps you up, try charging it in the kitchen. If breakfast is a scramble, decide on a protein source and have it pre-made and ready.

Build a backup plan for busy weeks, too. Two short strength sessions might be a manageable minimum, with more available when your schedule allows.

You can also lower the tension before it starts. Turning a vague intention into an if-then plan (“If coworkers order dessert, then I’ll grab a coffee”) has helped people follow through across hundreds of experiments.

Goals people pursue because they want to, rather than because they feel they have to, are linked to feeling fewer temptations in the first place. 

And plan ahead for nights out: in the smartphone study, heavy drinking and being around people who were already indulging made desires harder to hold back.

The Positive Corner of The Internet
About Arnold’s Pump Club Editorial Standards

We do things a bit differently here, starting with transparency.

1. The Content: All APC emails are researched, written, and fact-checked by the APC editors (see bottom of the email), with written contributions from Arnold (noted with “Arnold’s Corner”). Links take you to original studies (not second-hand sources).

2. Does AI play a role? Not for the primary content, but we use it in two ways. The main items are original content written by the APC team. The summaries at the end are AI-generated based on the human-written content above. We also use an AI tool to edit and review our interpretations of the research, ensuring scientific accuracy. We don’t assume AI is right, but we use technology to hold ourselves accountable.

3. Yes, we have partners (all clearly noted by “Together With”). Why? Because it allows us to keep the APC emails free. We first test products, and then reach out to potential partners who offer ways to help you improve every day. The bar is set high, and to date, we have turned down millions in ad deals. (Example: we will not partner with any non-certified supplements or those without evidence in human trials). If we won’t buy the product, we won’t recommend it to you. And if there’s no evidence it works, then there’s no place for it here.

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Publisher: Arnold Schwarzenegger​

Editors-in-chief: Adam Bornstein and Daniel Ketchell