Walk into any gym and you’ll overhear it. Could be someone telling their mate that crunches will burn belly fat, or that a woman doesn’t want to lift weights because they don’t want to get bulky. These myths spread quickly, usually because they’re simple, catchy and sound convincing. Social media has turbocharged the problem. Influencers with no personal training qualifications post confident advice, often based on their own experience, and before long it’s repeated as fact. Add in outdated ideas from old PE lessons and the fitness magazines of the 90s and it’s no wonder clients arrive with strong beliefs that aren’t supported by science.

Our job as personal trainers is not just to programme workouts but also to educate. A client might come to us genuinely worried about “ruining their knees with squats” or feeling guilty for eating pasta after 6pm. If we brush these concerns aside, we risk losing trust. But if we take the time to explain what the research actually says, in language they can relate to, we give them clarity, and that clarity often leads to better buy-in and better results.

So let’s look at ten of the most common myths, where they come from, and how we as coaches can talk clients through the facts.

1. Spot Reduction

For example, crunches help you lose belly fat

Most clients have heard that doing endless crunches will “melt away” their stomach fat. The logic feels obvious. If your abs burn, surely you’re burning the fat there too? But as you and I know, fat loss doesn’t work like that. Energy is drawn from fat stores across the body, not the muscle being exercised.

Studies on abdominal training have shown no difference in belly fat levels between people who trained abs and those who didn’t, when diet and overall activity were the same.

The message to clients is simple: “We’ll train your whole body and manage nutrition. Then your waistline will follow as overall body fat comes down.”

Some great research to read includes:

  • Vispute SS, Smith JD, LeCheminant JD, Hurley KS. The effect of abdominal exercise on abdominal fat. Journal of Strength and Conditioning Research. 2011;25(9):2559–2564. Click here to review the full research article.
  • Kostek MA, Pescatello LS, Seip RL, et al. Subcutaneous fat alterations resulting from an upper-body resistance training program. Medicine & Science in Sports & Exercise. 2007;39(7):1177–1185. Click here to review the full research article.

2. Static Stretching Before Training Prevents Injury

Many of us were brought up with PE teachers lining us up for toe-touches before football or netball. That routine stuck, and clients often feel they’re protecting themselves with a static stretch before lifting or running. The evidence, though, says otherwise. Static stretching alone doesn’t reduce injury risk.

What does work is a warm-up that raises temperature, rehearses movement patterns and gradually introduces load. Think dynamic drills, mobility work and skill-specific preparation.

For clients, the shift is reframing: “Stretching isn’t bad, but on its own it won’t keep you injury-free. Let’s warm up in a way that actually prepares your body for what’s coming.”

Here some interesting research around this topic:

3. Squats Wreck Your Knees

Few myths are as ingrained as this one. Everyone knows someone whose “knees went” from squatting, or so the story goes. But the research isn’t that clear cut. With proper technique and appropriate depth, squats are not only safe, they’re a powerful way to strengthen the muscles and connective tissues around the knee.

When a client voices this worry, it’s a chance to demonstrate. Start with bodyweight squats, focus on alignment and range, and show them how stable and strong it feels. Over time, as load is built progressively, the knee joint often becomes more resilient, not less.

If you’ve heard this myth before, have a read of these great studies:

Discover the Fitness Myths That Clients Believe on the TRAINFITNESS Blog

 

4. Lifting Makes Women Bulky

It’s a conversation most trainers have had. You have a female client who wants to “tone up” but fears heavy weights will make her look like a bodybuilder. Social media feeds this belief with dramatic before-and-afters taken out of context.

The truth is that muscle gain is a gradual process requiring sustained surplus, heavy training and often deliberate hypertrophy protocols. Most women will see improved strength, bone density, confidence and body shape long before any dramatic muscle mass appears.

The way to handle this myth is with reassurance and results: “We’ll train for strength and shape but not bulk. You’ll feel the difference long before you see it.”

If you’re training female clients and they are resistant to resistance training, read these:

  • Hubal MJ, Gordish-Dressman H, Thompson PD, et al. Variability in muscle size and strength gain after unilateral resistance training. Medicine & Science in Sports & Exercise. 2005;37(6):964–972. Click here to review the full research article.
  • Grgic J, Schoenfeld BJ, Davies TB, Lazinica B, Krieger JW, Pedisic Z. Effect of resistance training frequency on gains in muscular strength: a systematic review and meta-analysis. Sports Medicine. 2018;48(5):1207–1220. Click here to review the full research article.

5. Fasted Cardio Burns More Fat

It’s one of the oldest “hacks” in fitness. Do your cardio before breakfast and you’ll torch fat faster. And yes, in a fasted state, the body does rely more on fat during the session. But when you zoom out over weeks and months, there’s no difference in total fat loss compared to fed training if calories are controlled.

The real question is, which approach feels better and fits the client’s life? If they prefer training before breakfast, fine. If not, eating first is equally effective. Our job is to help them see the bigger picture, which is adherence and energy balance win out over gimmicks.

Have clients starving themselves before training? Read these:

  • Schoenfeld BJ, Aragon AA, Krieger JW. Effects of meal frequency on weight loss and body composition: a meta-analysis. Journal of the International Society of Sports Nutrition. 2014;11:54. Click here to review the full research article.
  • Hackett, D.; Hagstrom, A.D. Effect of Overnight Fasted Exercise on Weight Loss and Body Composition: A Systematic Review and Meta-Analysis. J. Funct. Morphol. Kinesiol. 2017, 2, 43. Click here to review the full research article.

6. Sweat as a Scorecard

“I must have had a great session. I was drenched!” Clients often link sweat to effort and results. But sweat is about cooling, not calories. Some people naturally sweat more than others and the exercise environment plays a huge role.

What matters is the work done including progressive overload, appropriate volume and recovery. Trainers can reframe this with a smile: “Sweat is just your body’s air-con. Let’s judge progress by strength, endurance and how you feel, not how soggy your T-shirt is.”

If you’re clients love to be dripping after training, read these:

7. DOMS as Proof of Progress

Delayed onset muscle soreness (DOMS) can make clients feel like they’ve “earned” their workout. The flip side? If they don’t ache, they worry they didn’t do enough.

Science tells us soreness mostly signals novelty, that is, doing something the body isn’t used to. It’s not a reliable marker of adaptation. Progress is better measured by strength increases, improved movement and consistency.

When a client complains they’re not sore, the conversation is: “That’s actually good. Your body is adapting. You don’t need pain to make gains.”

Read this if you have a client that’s a bit of a masochist:

  • Damas F, Phillips SM, Lixandrão ME, et al. Early resistance training-induced increases in muscle cross-sectional area are concomitant with edema-induced muscle swelling. European Journal of Applied Physiology. 2016;116(1):49–56. Click here to review the full research article.
  • Schoenfeld BJ. Does exercise-induced muscle damage play a role in skeletal muscle hypertrophy? Journal of Strength and Conditioning Research. 2012;26(5):1441–1453. Click here to review the full research article.

8. Grazing Every 2–3 Hours to Fire Up Metabolism

The old bodybuilding magazines were full of this advice. You have to eat small meals all day to “keep the furnace stoked”. It’s a belief many clients still hold.

But meta-analyses show meal frequency has little impact on daily energy expenditure or fat loss, provided calories and protein are matched.

For clients, the takeaway is personal preference. Some do well on three square meals, others like snacks. Our role is to help them find a pattern that supports adherence and recovery.

Are you training a compulsive grazer? Here’s some reads that will help:

  • Schoenfeld BJ, Aragon AA, Krieger JW. Effects of meal frequency on weight loss and body composition: a meta-analysis. Journal of the International Society of Sports Nutrition. 2015;12:4. Click here to review the full research article.
  • Cameron JD, Cyr MJ, Doucet É. Increased meal frequency does not promote greater weight loss in subjects who were prescribed an 8-week equi-energetic energy-restricted diet. British Journal of Nutrition. 2010;103(8):1098–1101. Click here to review the full research article.

9. Carbs After 6pm Make You Fat

“Eat carbs at night and they’ll turn to fat.” It sounds logical if you think in 24-hour cycles. But the body doesn’t reset at midnight. What matters is total daily intake. In fact, some research even suggests that evening carbs can support satiety and sleep, which in turn may aid fat loss.

When a client repeats this myth, we can reassure them: “What counts is your whole day’s nutrition. Having pasta at dinner isn’t the enemy, it can actually help you recover and rest.”

Carbophobic clients? Here’s your research:

10. Turning Fat into Muscle

Clients often look at transformation photos and assume fat has literally turned into muscle. It’s easy to see why the idea sticks. But physiologically, fat and muscle are separate tissues. You can lose fat while gaining muscle, but one doesn’t “convert” into the other.

This is where education matters: “We’ll help you reduce fat through diet and activity, and build muscle through training. Both can happen at the same time, especially for beginners. But they’re two different processes.”

Beef up your knowledge with these great studies:

  • Phillips SM. A brief review of critical processes in exercise-induced muscular hypertrophy. Applied Physiology, Nutrition, and Metabolism. 2014;39(11):1171–1178. Click here to review the full research article.
  • Stokes T, Hector AJ, Morton RW, McGlory C, Phillips SM. Recent perspectives regarding the role of dietary protein for the promotion of muscle hypertrophy with resistance exercise training. Frontiers in Physiology. 2018;9:1796. Click here to review the full research article.

Wrapping Up

Myths will never disappear. They’re sticky, easy to share and often more appealing than the truth. But as fitness professionals, we’re in a unique position to challenge them. Not with lectures or jargon, but with clear explanations, relatable metaphors and, most importantly, results that speak for themselves.

Every time we take a myth and replace it with fact, we do more than educate. We help clients trust the process, commit to the programme and see that evidence-based training really does deliver.

From Confusion to Credible. Begin with CIMSPA-Recognised Training

Most people who step into the fitness world have already been bombarded with misinformation. In fact, surveys suggest around 70% of gym-goers still believe common fitness myths like “spot reduction works” or “lifting makes women bulky.” That’s why our entry-level courses at TRAINFITNESS don’t just prepare you for a new career, they also give you the knowledge to separate fact from fiction. Whether you’re looking to become a personal trainer, gym instructor, yoga or Pilates teacher, exercise to music leader or childrens fitness instructor, every course is CIMSPA recognised and built to give you a rock-solid foundation in exercise science, coaching, and client support. Perfect if you want to start your professional journey in fitness or if you’re simply ready to understand the truth behind the myths that hold so many people back.

View all our courses where you can become a fitness professional here.