Gut Health for Lifters: Bloating, Fibre and Digestion

Variety matters as much as amount

A large citizen-science study, the American Gut Project (McDonald and colleagues, mSystems, 2018), found that people who ate more than 30 different types of plant a week had more varied gut bacteria than people who ate 10 or fewer. A more varied gut community is generally considered a sign of a healthier gut.

Plant types include fruit, vegetables, beans, whole grains, nuts, seeds, herbs and spices. Swapping a single bag of frozen broccoli for a mixed bag of vegetables, or adding a handful of mixed seeds to your oats, adds variety with no extra effort.

Fermented foods

In a 10-week study at Stanford (Wastyk and colleagues, Cell, 2021), people who ate more fermented foods, such as yoghurt, kefir, kimchi, sauerkraut and kombucha, ended up with more varied gut bacteria and lower markers of inflammation. Interestingly, the high-fibre group in the same study did not see the same change in that time, which suggests both matter in different ways.

A serving or two a day is an easy place to start. Greek yoghurt or kefir doubles as a protein source.

Common culprits for lifters

Protein powders

• Whey concentrate contains some lactose. If dairy upsets you, a whey isolate (much less lactose) or a plant protein may suit you better.
• Some powders add gums, sweeteners or extra fibre that can cause bloating in some people. Try a simpler product with fewer ingredients.

Protein bars and "low sugar" snacks

Many use sugar alcohols such as maltitol, sorbitol or erythritol (check the label for "polyols"). In larger amounts they commonly cause gas, bloating and loose stools.

Eating a lot of food on a bulk

When calories are high, the sheer volume of food can be the problem:

• Spread food over four or five meals rather than three huge ones.
• Use some less bulky carbohydrates, like white rice, bagels, juice or dried fruit, alongside the high-fibre foods.
• Liquid calories, like a milk-and-oats shake, can help when you feel too full.

Lean bulk: how fast should you gain weight? also helps you avoid eating more than you need.

Caffeine, pre-workouts and stress

Large amounts of caffeine and some pre-workout ingredients can upset the stomach. Stress and poor sleep affect digestion too, which is one reason they are worth tracking. See sleep and muscle growth.

What about probiotics and gut supplements?

Probiotic supplements are not one thing: each product contains different strains, and research results for one strain do not apply to another. Some have good evidence for specific problems, such as certain types of diarrhoea, but for healthy people looking to "improve gut health" in general, the evidence is mixed. Food first (fibre, plant variety and fermented foods) is the better-supported starting point.

When to see a doctor

See a doctor rather than experimenting with your diet if you have any of these:

• Blood in your stool, or black, tarry stools
• Unexplained weight loss
• A lasting change in bowel habits, especially if you are over 50
• Severe or persistent pain in your abdomen
• Difficulty swallowing, or vomiting that does not settle
• Symptoms that wake you at night
• A family history of bowel cancer, coeliac disease or inflammatory bowel disease

If you have frequent symptoms with none of those warning signs, such as ongoing bloating, cramping or alternating constipation and diarrhoea, your doctor can check for things like irritable bowel syndrome (IBS) or coeliac disease. Dietary approaches for IBS, such as the low-FODMAP diet, are best done with a dietitian, because they are meant to be temporary and can cut out foods you do not need to avoid.

Where coaching helps

Digestion is easier to fix when someone is watching the pattern. With one-to-one coaching from CoachAk, your weekly check-in includes a space for digestion notes alongside your weight, training, nutrition, sleep, energy, hunger and stress. Your coach can see what changed in the weeks you felt bloated or off, and adjust your food choices and meal structure, while anything that needs a doctor goes to a doctor.

If you want a plan that works for your body and your stomach, apply for coaching.