It’s easy to complicate fitness and nutrition by reading through research papers or someone’s take on the research. We want definitive answers, which is why a conclusion in a research paper that reads ‘XYZ may assist body composition and further studies are required for confirmation’ turns into an article headline of ‘XYZ - the new science-based way to rapidly improve body composition’.
A bit of research and complication can be a good thing. Maybe you’re looking to start a training program and find some research demonstrating the benefits of running for cardiovascular health. This knowledge drives adherence to the running program because you want to get those benefits, which is a good outcome.
But complications can also have their downside. If adherence is not perfect, it can force you to become unnecessarily rigid with your training or nutrition and feel like you’ve failed. Using the running example above, if you can’t lace up and get out there, you don’t do any other form of exercise because it won’t have the same benefits as running.
Trying to find the best time of day to exercise is a classic example of overcomplicating your training program.
You might have heard that strength training in the early afternoon is optimal due to hormonal and temperature cycles or that training in the morning is superior for losing body fat because blood glucose is low, increasing the oxidation of fatty acids from the bloodstream.
Both are correct, but the magnitude of their impact is minimal. The training principles of frequency, intensity and duration are more important to improving strength, fitness and body composition.
The best time of day to train is whenever suits your routine and allows you to adhere to your training program. Whether this is morning, lunchtime or evening sessions will have almost zero impact on your results.
Someone who lifts weights four times a week across morning, lunchtime and evening sessions will get better results than someone who trains twice per week at 2:39 pm when their hormones and body temperature are optimised for strength gains.
So instead of advising when to train to optimise physiological response to exercise, let’s discuss the rigid and flexible approaches to planning your training for optimal adherence.
The Rigid Approach
The rigid training approach commits to morning, lunchtime or evening training sessions frequently that are typically scheduled in advance. The time depends mainly on what suits the individual and their commitments alongside other participants.
The rigid training approach lends itself to progressive overload because training sessions are predictable and consistent.
The downside of rigid training is that the training mindset can reflect the structure. People get used to training in the morning on an empty stomach and subsequently struggle to exercise later in the day. This can be a real issue for people training for sports or events that require performing at a different time of the day.
Many people with rigid training schedules can adopt an all-in approach and dislike changes. If they are morning trainers but cannot get their session in due to breakfast meetings for a week, they won’t train in the afternoon even if they have the time.
Despite these downsides, a rigid training approach suits most people because planning their training sessions helps with adherence. Not many people want to wake up earlier or get home later so they can get their training session in. However, they realise that allocating time for the session is critical to completing the training if it is to be a priority for them.
The Flexible Approach
The flexible training approach is reactive and training sessions fit where it suits the individual. A significant variable here is how necessary training is to the individual, determining where exercise will fit in the priority. The flexible trainer can return from Saturday brunch and head out for a 10km run.
Many people think flexible training requires less discipline than rigid training, but the opposite is true. Success in a flexible training program requires continuous exercise prioritisation and commitment to complete sessions at suboptimal times.
This approach is common for people who travel a lot or with young families. They still have training objectives and programs, but the sessions are completed when possible.
I’ve previously discussed since COVID, a few of my clients are using shorter training sessions with much higher frequency. Instead of four 30-minute sessions per week, they might do 12 10-minute sessions. Much of the time these are on certain days and at certain times, but they can also be flexible across the week.
What’s Best for You
Many people think that flexible training is the beginner option and you progress to being more rigid. However, most people go the opposite way - they become more flexible with their establishing training programs when fewer commitments allow them to do so.
A longer training duration typically requires a rigid. If your bike ride will take two hours, getting up early is the only option for most people. Taking your laptop to link into Teams meetings is terrible for your aerodynamics.
Many people believe you start with a flexible training program and then become more rigid as the program progresses to be more structured. However, the opposite is generally true. Most people start out requiring allocated time to exercise to build adherence and begin seeing the results of their work.
Once you’ve got a solid level of adherence to the program, it becomes easier to have greater flexibility in training.
As you progress and more frequency or duration of training sessions is required to advance, the rigid approach may be necessary to complete all training sessions.
My training scheduling is quite rigid, especially when the program calls for cardio. Running in 90%+ humidity on the Gold Coast is hard enough for me, so I will always try to avoid running in hot sun.
I also prefer doing cardio on an empty stomach, so this means running in the morning before the sun rises is the only way I’ll be doing cardio that day.
I cannot understand how people up here can run outside at 12pm when it’s 30 degrees and humid. My cardiovascular system could not take that stress, so I’ll stick to jogging around with a sunrise instead of cooking at lunchtime.
If I have to be somewhere early on a cardio day, I either get up earlier or change my training around to do cardio another day.
In summary, starting with a rigid approach suits the majority as it allows the routine to be developed. Once adherence is solid, switching to a flexible approach might better suit your lifestyle.
The focus should be on finding what training approach works best for you. Forget about there being an optimal time of day to train. Any training is optimal for most people!
Agree re: running in the heat in the middle of the day...I see people doing it here in Texas in the summer all the time! I don’t think it’s good for you, but as you say, if that’s what’s optimal for you...