12 More Lifting Myths: Technique, Nutrition and Age

After a first set of twelve stubborn beliefs, here are twelve more. These mostly concern technique, nutrition and assumptions about what is possible depending on your age or your starting point. As in part one, most of them did not come from nowhere: they rest on a real observation whose context has gradually been stripped away.

About training

1. You have to lift heavy to build muscle

Heavy loads are essential for maximal strength, which is highly specific to the loads you train with. For muscle growth, the window is considerably wider than people assume.

Sets performed with moderate or even light loads can produce comparable hypertrophy provided they are taken close enough to failure. Load then becomes a matter of convenience and practicality rather than a requirement. That does not make heavy work pointless: it remains more time-efficient, easier to track in a log, and necessary if strength is your goal.

2. A muscle should only be trained once a week

This rule comes from bodybuilding programmes where each session piled a very high volume onto a single muscle group, which justified a long gap before returning to it.

At matched weekly volume, spreading that volume across two sessions rather than one generally produces at least equivalent results, with shorter sessions and better execution quality towards the end. Frequency then becomes mostly a scheduling question, as covered in our article on training frequency per week.

3. Bodyweight training cannot build muscle

A muscle does not distinguish where the tension it experiences comes from. What matters is the level of effort produced and your ability to increase the difficulty over the weeks.

The real obstacle with bodyweight exercises is therefore not their nature but progression: adding two kilos to a bar is straightforward, making a push-up harder is less so. There are levers for it though, such as unilateral variations, range of motion, slowing the descent or adding external load. We cover this in our guide to home workouts.

About technique

4. Your knees must never travel past your toes

This cue was meant to reduce stress on the knee joint. It does have a real effect, though one rarely mentioned: the stress removed from the knee is transferred to the hips and lower back.

In daily life your knees pass your toes on every flight of stairs you walk down. In a squat, forward knee travel is normal and depends on your proportions, your ankle range and the variation you use. There is no general reason to prevent it artificially in someone who has no pain. The things that genuinely deserve attention are in our article on squat technique mistakes.

5. A rounded back is always dangerous

The spine is built to flex, and flexion is not in itself an injury. Current evidence does not support the claim that a slightly rounded spine systematically causes damage.

That said, the nuance should not become a blanket permission. Under heavy load a neutral position remains the default: it transmits force more efficiently, it is more repeatable and easier to control. Progressive rounding that appears set after set usually signals a load that is too heavy or fatigue setting in. Where there is pain or a history of back problems, professional advice takes precedence over any general rule. Our article on the deadlift goes into this.

6. You should suck your stomach in when lifting

Pulling the navel towards the spine is a common cue, but it reduces the pressure you can generate inside your abdomen, and therefore the stiffness of your trunk under load.

For heavy efforts, the strategy generally preferred is to breathe into the belly and then contract outwards, as though bracing for a punch. The stomach does not pull in, it hardens. On light loads and long sets this level of bracing serves no particular purpose and continuous breathing is enough.

About nutrition

7. You cannot absorb more than 30 g of protein per meal

That figure comes from studies measuring the protein synthesis response over only a few hours, which created the impression of a ceiling. More recent work over longer timeframes shows that considerably larger amounts continue to be used by the body.

In other words, a very high-protein meal is not wasted. Spreading intake across three to five servings remains practical and probably slightly preferable, but it is not a strict physiological constraint. What matters most is the daily total, as explained in our article on daily protein intake.

8. You need six meals a day to boost your metabolism

Digestion does consume energy, but that cost is proportional to how much you eat, not to how many meals you split it into. Three 700-calorie meals and six 350-calorie meals produce the same total.

Meal frequency is therefore a matter of comfort, appetite and how your day is organised. Some people stick to their diet better with a few large meals, others with frequent smaller ones. Neither option speeds up your metabolism.

9. Fat burners make you lose weight

The large majority of these products are built on caffeine and plant extracts whose measured effect on weight loss is small or absent when tested rigorously.

Where an effect does appear, it usually comes from a slight rise in energy expenditure or a reduction in appetite, neither of which replaces a calorie deficit sustained over time. Some products sold online have also been found to contain undeclared substances. Our article on supplements worth taking sorts through them, and any product taken alongside a condition or medication should be discussed with a doctor or pharmacist.

About the body and results

10. You cannot build muscle and lose fat at the same time

It is difficult but not impossible, and some situations lend themselves to it particularly well: the first months of training, a return after a long break, or a higher starting body fat level.

The process becomes considerably slower in a trained lifter close to their potential, where separating phases is usually the better option. In every case the scale alone will not show it, since the two changes offset each other. We cover this in our article on body recomposition.

11. Lifting stunts teenagers' growth

This fear comes from the idea that load might damage growth plates. Current position statements from paediatric and sports medicine bodies consider resistance training safe and beneficial for adolescents when it is properly supervised.

The documented problems overwhelmingly involve poorly supervised maximal lifting, technique that was never taught, or progression that was far too fast, all of which apply at any age. Supervision therefore matters more than age itself. For a teenager, medical advice before starting remains the most sensible step, particularly where there is joint pain or a previous injury.

12. Past a certain age it is too late to start

The capacity to gain muscle and strength declines with age, but it does not disappear. Meaningful gains are documented in people starting at sixty and beyond, including in strength, bone density and everyday independence.

What changes is the rate of progress, the importance of warming up and the need for slightly longer recovery. We go further into this in our article on lifting after 40. As always, medical advice before starting is recommended, especially where a known condition is involved.

What these beliefs still have in common

As in part one, most of these myths are not inventions. They are safety cues that hardened into prohibitions, numbers from one specific protocol turned into laws, or bodybuilding habits taken out of context.

Two reflexes limit the damage. First, ask where the number came from: measured in whom, over how long, under what conditions. Second, separate a safety rule that is useful for a beginner from a universal physiological truth. A great deal of advice belongs to the first category and is presented as belonging to the second.

Frequently asked questions

Should beginners avoid machines?

No, they are often a good entry point. They guide the movement, reduce the stabilisation demand and let you train hard safely while technique is being built on free weight exercises. Both formats can coexist from the first weeks.

Does lifting make you less flexible?

Not when performed through a full range of motion. Training into lengthened positions generally improves mobility rather than reducing it. Losses of flexibility usually come from consistently partial ranges or from a complete absence of joint work.

Should you train fasted to burn more fat?

Your body does use more fat during fasted exercise, but that does not translate into greater fat loss over time, since the balance is struck across the whole day. The choice is therefore about digestive comfort and performance, not effectiveness.

Are supplements necessary to make progress?

No supplement is essential. A few have solid evidence behind them and can offer a modest benefit, but they come after training, nutrition and sleep, never instead of them. Insufficient protein or calories cannot be compensated for with a powder.

What both sets of myths have in common is that they can be argued about endlessly until you have your own numbers. Whether your frequency suits you, whether your loads are genuinely rising, or whether swapping an exercise helped you progress cannot be deduced from an article: it is read from a history. In Musku you have your sets per exercise, your records, your progression and how your volume is distributed across muscle groups. It is the simplest way to replace a belief with an observation.