Build muscle as an athlete, without giving up running

Building muscle takes three things: a slight calorie surplus, enough protein, and strength training. You can still run at the same time. You set your target weight, with or without a date. Trainetic calculates your needs from your profile, adds what today's session costs, and gives you a target for calories, protein, carbs and fat. It never imposes a menu: your food log shows you where you stand.

Share this guideWhatsApp Facebook LinkedIn X Email

Get notified

Five rules for successful muscle gain

They come from sports nutrition research and from research on concurrent training, strength and endurance.

A moderate surplus. A few hundred calories above your needs is enough. A bigger surplus mostly adds fat.

A slow gain. A quarter to half a percent of your body weight per week: that is the recommended rate for the gain to be mostly muscle.

Enough protein, without excess. Beyond about 1.6 g per kilo per day, studies find no additional muscle gain.

No strength training, no muscle. The surplus fuels the building; strength training is what triggers it.

Running and building muscle go together. Recent analyses find no notable effect of endurance training on muscle gain; it mainly slightly limits explosive strength.

The safeguards built into your muscle gain goal

They apply automatically, and every adjustment is explained to you.

Benchmark	In Trainetic
Default surplus	300 kcal per day above your needs
Maximum surplus	500 kcal per day
Maximum rate	0.5% of your body weight per week
Protein	1.8 g per kilo of body weight per day
Training days	Your target goes up by what the session costs on top of rest

With a scale that measures body composition, Trainetic alerts you if more than half of the weight gained is fat mass, over at least three weeks of measurements.

How Trainetic supports your muscle gain

Nutrition is calculated; training is built alongside it.

A target calculated every day

Your baseline needs, a moderate surplus, and today's session: your target moves with your training, so running does not eat up your surplus.

Protein and carbs set for you

1.8 g of protein per kilo, and a share of carbs adapted to your training: enough to build muscle and get through your endurance sessions.

A training plan that can include strength work

When you create your running training plan, you can add strength training sessions, with the subscription.

When this feature is not for you

If you are pregnant, under 18 years old, on medication, or if your relationship with food is difficult, talk to your doctor first: a weight goal should not be set on your own in these situations. If you think you may have an eating disorder, talk to your doctor: they can point you to the specialist support service in your country.

Five muscle gain mistakes

Eating "everything in sight". Too big a surplus makes you gain weight fast, but mostly fat.

Forgetting strength training. Without strength work, the surplus does not turn into muscle.

Piling on protein. Beyond 1.6 to 2 g per kilo, it no longer adds extra muscle.

Dropping endurance completely. Nothing requires it: it barely gets in the way of muscle gain, and your heart benefits from it.

Judging after two weeks. Muscle builds slowly. What matters is the trend over several months.

Where these figures come from

Every benchmark on this page comes from a public source.

The moderate surplus and the rate of a quarter to half a percent of body weight per week: review by Iraki et al. (Sports, 2019).

The protein plateau around 1.6 g per kilo: meta-analysis by Morton et al. (British Journal of Sports Medicine, 2018). The International Society of Sports Nutrition recommends 1.4 to 2 g per kilo.

The effect of endurance training on muscle gain: meta-analysis by Schumann et al. (Sports Medicine, 2022, 43 studies) — no notable effect on muscle size or maximal strength, a small decrease in explosive strength.

Common questions about building muscle

How many extra calories do you need to build muscle?

A few hundred per day. Trainetic starts at 300 kcal above your needs and never goes beyond 500.

How much protein per day?

Around 1.6 to 2 g per kilo of body weight. Your target is set at 1.8 g per kilo, spread across your meals.

How many kilos can you gain per month?

At the recommended rate, a quarter to half a percent of body weight per week, a 70 kg athlete gains about 0.75 to 1.5 kg per month. Your rate of gain is capped at 0.5% of your body weight per week.

Can you build muscle while still running?

Yes. Recent studies find no notable effect of endurance training on muscle gain. What matters: a surplus that takes your sessions into account, and strength training.

Do you need mass gainers or supplements?

No, not necessarily. Eating enough, with enough protein, covers the needs of most athletes.

What if I would rather lose weight, or maintain it?

Same feature, different goal: lose weight or maintain your weight.

Is it free?

Yes: setting your goal, tracking your intake, searching for and scanning your foods. Access only requires your consent to the processing of this health data. Automatic estimation of a food or a dictated meal is included in a limited amount, with more under the subscription.