Exercise alone won’t help you build muscle or burn fat—here are three key nutrition lessons I learned when undertaking my own fitness transformation

A few years ago, I had the opportunity to complete a 10-week body transformation under an expert’s supervision.

The workouts were intense, the learning curves were steep, and the results—in my humble opinion—impressive.

Over 70 days, I packed on 7kg of lean muscle—then promptly lost it all in a matter of weeks.

While the process taught me about what works for my individual needs, it also opened my eyes about what doesn’t work, and how hard it is to make lasting changes.

Above all, it made me realize that the success of any workout plan will largely be dictated by what you do in the kitchen.

To that end, here are three nutrition rules I believe will best support your fitness goals in 2026.

1. Establish your calorie baseline

Whether you’re starting a new Pilates plan or training for a parkrun, increasing the time you spend working out will increase your nutritional demands.

It’s important to get a read on how many calories you usually consume to understand if you need to increase or decrease your intake accordingly.

As a general rule, you’ll want to make sure you’re in a calorie surplus if your primary goal is muscle gain. If you’re trying to lose weight, you’ll need to be in a calorie deficit.

When I first started on my muscle-gain plan, I discovered I barely hit 2,500 calories per day. To support my hour-long gym workouts and add muscle, I needed to double this intake.

You can use an app like MyFitnessPal to try and estimate your baseline calorie intake and expenditure.

2. Count calories—but don’t obsess over them

Tracking calories will keep you on course for your long-term goals, especially if you’re trying to noticeably change your body composition.

But it’s easy to get bogged down in the numbers if you count them all day, every day.

My preferred approach is to track calories once on a typical working day, then again on a typical day off, such as on the weekend.

This should give you a good idea of how your intake fluctuates throughout the week.

Repeat this process at regular intervals, such as every week or month. You may need to adjust your intake if the workouts in your training plan become more or less demanding.

3. Strive for sustainable habits you can stick with

One of the biggest mistakes I made during my transformation was trying to overhaul my fitness and diet in a short 10-week window.

It meant cramming in workouts and calories at an unsustainable frequency, loading my days with late-night workouts, three-course dinners and unappetising midnight feasts.

Were I to do it again, I’d take my time, allowing my body and routine to adapt gradually.

If you’re also looking to add muscle or lose weight, I’d suggest aiming to increase or decrease your daily calorie intake by no more than 5-10% at first.

That will make the whole process feel more sustainable.

If progress stalls, then you can make another 5-10% adjustment. Give your body time to adjust to the process and take things slowly.