The fitness industry, TikTok, and your gym buddies are full of ideas about when the best time to weight train is, when to eat, and which days to skip. Some of it might be solid advice, but wading through the misinformation and speculation can be more exhausting than bench press drop sets after a hard day in the office.
Michael Betts, director TRAINFITNESS, knows this all too well. “Whether you’re a beginner or a gym veteran, you’ve probably heard one or more of the following:” he says.“‘Training in the morning is better for fat loss; training in the evening builds muscle; you should skip Fridays and train on Mondays.”
It’s kind of confusing. But, as Betts explains “Our bodies don't operate on a stopwatch, and while some timing strategies can have an impact, they aren't anywhere near the most important factors for driving results.”
Here, then, is a guide to how and when you should train, backed by actual experts with decades of expertise in getting people absolutely ripped.
When you can train depends largely on your schedule, but a post-lunch sesh might yield the best results. Both Betts and Adam Enaz, founder of Enaz Fitness, are big proponents of a mid-afternoon weights session.
“Performance does actually vary across the day,” says Betts. This meta-analysis, published in Chronobiology International in 2019 shows that our strength and power output will generally peak in the late afternoon or early evening, largely because our body temperature is higher, the nervous system is firing more effectively, and we've been awake long enough for the muscles to properly activate.
“The strongest window for the average person is roughly 14:30 to 20:30,” adds Enaz. (So, in America that's 2:30 p.m. to 6:30 p.m.) In fact, one 24-week study published in the peer-reviews journal Applied Physiology, Nutrition, and Metabolism, found strength improvements at any time of day, but a greater muscle gain in the evening.
“That said, the advantage is usually small,” Enaz clarifies. “You shouldn’t underestimate going by feel; if you train far more consistently in the morning, you should get better results despite not training in the ‘biologically optimal’ window.” And if training in the evening makes it harder for you to sleep, you should take into account what's best for your recovery plan as well.
“What matters most is what happens over weeks and months,” says Betts. “When a person trains consistently at the same time, their body adapts to perform at that time.”
The fastest vs. fed debate tends to apply more to cardio workouts than weight sessions for one good reason: if you’re hefting your own bodyweight, you need energy to be able to do it. That said, for lighter weights sessions like a HIIT circuit, or even a calisthenics workout, a fasted session could help you tone up while you work.
In actuality, when it comes to muscle and strength gains, the evidence shows no real advantage either way. A 2025 meta-analysis published in the Journal of Bodywork and Movement Therapies studied fast vs. fed resistance training and found that the results—barring fat loss— were more or less the same.
But what about eating post gym to lock in those gains? To what degree does the anabolic window apply? “The idea that protein must be consumed within 30 to 60 minutes of training to maximize muscle protein synthesis has been repeated so often it's treated as fact,” says Betts. “But, a meta-analysis of 23 studies involving over 500 participants found that timing protein around workouts added no meaningful benefit for muscle growth or strength.”
Rather than when you eat, total daily protein intake was most important. “Hitting your daily protein target (~1.4–2.0 g/kg) is by far the most important consideration,” adds Laith Cunneen, exercise physiologist and founder of Peak Physio. “If you've eaten within 4-6 hours of training, the post-workout ‘window’ is less critical, but if you’re training fasted, it may be beneficial to prioritize eating sooner.”
Hitting the rower or the treadmill alongside your bench sets? Then it’s likely that, over the years, different gym sages have advised you on which order is best for maximizing gains, and fat burn. Maybe a sprint session supercharges the metabolism before weights. Maybe walking on the treadmill at the end helps to preserve progress, and is all the cardio you need.
For Betts, hitting both on the same day might not be the most effective way to ensure muscle growth. “The concern is simple: resistance training and training for endurance trigger different adaptive responses in our muscles, and if we do both at the same time, then there's a risk that signals conflict and reduce the effectiveness of each,” he says.
Betts points to a meta-analysis in the Journal of Strength and Conditioning Research which found that concurrent training can reduce strength increases and muscle growth, but the type of training plays a huge role in this, with running producing more interference than cycling, for example.
For Betts, it’s best to separate the two, rather than depleting glycogen stores on the step machine before going for a clean and press PB. “If you must combine both kinds of training in one day, the research points towards lifting first and, if you can, separate them by at least three hours,” he says.
Anecdotally, you may feel freshest on a Monday and become increasingly more fatigued as the week goes on. Enaz says there’s little scientific evidence to back that up, but it makes sense that we feel stronger after a weekend of good eating and recovery. “Friday fatigue, though, is real,” he says. “This is because we accumulate sleep debt, work stress, and lower recovery as the week progresses.”
Worse of all, Enaz says that stressful workdays can reduce training quality, with “mental fatigue (deadlines, cognitive load, poor sleep, long shifts) all reducing our willingness to push close to failure, which is vital for hypertrophy training.”
“Schedule your heaviest,vmost technical sessions on the days you feel most recovered,” he advises, “reserving days you’re not feeling it for easier sessions.”
For Cunneen, twice a week is enough for major muscle groups. “While there’s always debate, a 2016 meta-analysis showed that training each muscle group twice per week produced superior hypertrophic outcomes compared to once weekly, even when total volume was matched,” he says.
Meanwhile, a 2023 paper in the British Journal of Sports Medicine found higher-load, multiset, twice-weekly training was the most effective prescription for hypertrophy, whilst thrice-weekly was optimal for strength.
“A practical four-day push/pull schedule might run: push on Monday, pull on Tuesday, rest on Wednesday, push again on Thursday, pull on Friday, then rest over the weekend,” Cunneen says. “This hits each movement pattern twice weekly with 48-72 hours between sessions targeting the same muscle groups.”
Ultimately, when and how you’re working out isn’t quite as important as finding a plan that works for you, and sticking to it. “Looking across the research on timing, frequency, and program structure, it’s clear that adherence sits at the top of the hierarchy,” says Betts. “Training three times per week for a year beats perfect programming for three months. When it comes to building long-term muscle and strength, nothing else comes close to the importance of showing up consistently.”
This story originally appeared in British GQ.