Five Filters for Fitness Coaches

What really works?

What works fastest?

What’s the proof?

Double-blind, randomized, peer-reviewed studies–that sounds like science, doesn’t it? But even the stuff that’s published in scientific journals is subject to bias. Sometimes “peer-reviewed” means “rubber-stamped”. And sometimes scientists draw the wrong conclusions from good data. Sometimes people even write stuff that looks like science because they want to sell their snake oil!

Information is everywhere. The public is overwhelmed, and so are most coaches. Most of us quickly become skeptical of anything we haven’t seen with our own eyes, and eventually become cynical of everything in the industry.

Unfortunately, you and I don’t have the luxury of arguing about theory in a University office somewhere: we have to get our clients results. Our livelihood depends on it. Eventually, we’ll have to DO something.

Here are five functional questions I ask before I apply any training method; any diet; any new idea in fitness. I call them The Five Filters and try to teach them to my clients. (Gym owners: here’s your list of Five Filters.)

  1. “Have you done it yourself?” This is the basic requirement for further conversation, especially online. It’s surprising to see how many experts will advocate a training method or diet without actually doing the thing. Unfortunately, that doesn’t stop unscrupulous “experts” from arguing for–or even selling–their idea. The first element of proof is n=1 (one person actually did the thing; it’s not just something they dreamed up.)
  2. “What results did you get, exactly?” How did they track and measure their progress? Did they really lose 20lbs on the Ketogenic Diet, or was it 17lbs? The first problem with self-reported results is imprecise measurement. “I lost a TON of weight on that diet!” is meaningless–unless the person literally lost 2,000 pounds. I want to know exactly how much weight they lost.
    If they lost exactly 20lbs on the Ketogenic Diet, how much of the weight was water? How much was muscle? How much was fat? You can go too far down the rabbit hole here, but if the subject didn’t measure anything–if they’re just estimating–then I discard their opinion.
  3. “Compared to what?” What else has the expert tried?  As coaches, we’re not limited by choice. We’re never comparing the potential of doing Paleo against the potential of doing nothing. We’re comparing Paleo against Zone or Keto or caloric restriction.
    Then I can follow up with, “What else have you tried?” and compare their results on the Paleo diet against their results on the Zone diet. Because if the subject has ever only tried one diet, of course they got great results!
  4. “Have you coached someone else to do it?”
    You and I know there’s a massive difference between what we can do and what we can get a client to do. Some clients are stricter than I am. Some clients have more willpower than I do; some have less. Some clients have spouses that support their habits; some have spouses that complain about any changes in diet and exercise habits.
    We work in gyms. We have 24-hour access to everything we need to be successful. That doesn’t mean an idea is translatable to our clients.
    For example, we could advocate Dan Duchaine’s Body Opus Diet (five days of zero carbs, then heavy carb ingestion every two hours over the weekend. The first meals in the carb-up are icing sugar and Froot Loops. I’ve done it. I’d never get a client to do it.)
    That’s an extreme example, but think about our recommendation to have a client do ten minutes of mobility work before class; then a foam roller roll-out after class. Most people just don’t have that kind of time. When the mobility salesmen come knocking and tell me that I should include their mobility videos in every class, I ask: “How have you incorporated this into classes at YOUR gym?”
  5. “Can you do it more than once?” Sometimes, the cost of a new training strategy is so high that your client can only do it for a short time. For example, I have a $2400-per-year budget for a cycling coach. I can spend that all at once on a week-long cycling camp, or I can pay $200 per month for programming. What’s better?
    This is especially important with diet. Sure, cutting carbs from your diet might get someone dramatic weight loss (or maybe not…see the first Four Filters). But can you do that for the rest of your life? Can your client? What happens when they start eating carbs again?
    In other words, what’s the real cost of this idea? Will it stop you from continuing? Will it harm you in the long term? Is it sustainable?


Science exists not to prove, but to disprove. Coaches are wise to maintain a healthy dose of skepticism. But it’s easy to become paralyzed by cynicism; eventually, we have to DO something. The key is to filter out the bad or unproven ideas and get to the good ones faster.

Leave a Reply

If you'd like to be sure you dont miss any of the valuable content we publish, just subscribe here.

If you'd like to continue the conversation with us, simply hit reply to the next email that hits your inbox. We love to hear from our followers!