Running Doesn’t Wear Out Healthy Knees. The Real Risk Is Something Else.

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Today’s Health Upgrade

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.

Together With Sundays For Dogs
Are You Overheating Your Dog's Dinner?

We've gotten pretty good at side-eyeing our own food. We read labels, know "ultra-processed" is a red flag, and mostly accept that something cooked hot and fast in a factory isn't the same as something cooked at home.

Then we scoop a bowlful of little brown pellets and don't think twice. But the science suggests it might be worth a second thought.

Most kibble is made by extrusion, a process that blasts ground ingredients with heat and pressure and pushes them through a die like Play-Doh. The temperatures involved can top 300°F.

At that heat, food undergoes chemical changes. Protein and sugars react to form compounds, and researchers have found that their levels in commercial pet food fall within the same range as those in heavily processed human foods.

That same heat damages the protein itself. Some of a food's lysine (an essential amino acid) gets chemically locked up during cooking, so the body can't use it, and kibble tends to lose more of it than gently cooked food does.

One 2026 analysis of 41 dog foods found that fresh options carried roughly twice as much usable lysine as kibble — partly due to better ingredients, partly to gentler processing. 

Cook protein hard enough, and you get something like a steak left under the broiler until it's a hockey puck.

Research on these compounds is extensive in humans and still catching up in dogs. The picture's messier than the marketing: wet and canned foods actually test highest for these compounds, not kibble, and nobody's proven your dog's kibble is making them sick. If that's what you feed, your dog is probably fine.

But you can feed your dog without turning mealtime into a project.

So we went looking for real food that skips the high heat without becoming a raw-handling project.

The best we found was Sundays For Dogs.

Sundays is air-dried low and slow from human-grade meat, fruit, and veggies. Not extruded, not blasted at 300°F.

Gentle drying preserves nutrients like raw, and every batch is third-party tested for pathogens like Salmonella and E. coli and run through a full nutrient analysis, so there's no thawing, no mess, and no food-safety tightrope.

It's vet-founded, and its beef and turkey recipes are AAFCO complete and balanced for all life stages, including large-breed puppies.

Dogs picked the Sunday’s chicken recipe 39-0 over premium kibble in an independent taste test. No fridge, no prep. Scoop and serve.

Sundays for Dogs gets our stamp of approval.

Use code PUMPCLUB for 50% off your first order, and give your dog the same attention to their nutrition you give your own.

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.

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Publisher: Arnold Schwarzenegger​

Editors-in-chief: Adam Bornstein and Daniel Ketchell