“The concept of aligning exercise with your chronotype — whether you’re naturally more of a morning or evening person — is gaining traction, and for good reason,” according to Kovacs.

“From a physiological standpoint, your body’s hormonal profile, core temperature, and neuromuscular readiness all fluctuate across the day, which can influence performance and potentially long-term health outcomes,” he explained.

With so many variables, it can be difficult to figure out what the best time to exercise might be, on a day-to-day basis.

“For most individuals, the ‘best’ time to exercise is the time they can consistently commit to,” Kovacs noted. “That said,” he added, “if you want to optimize, there are a few practical indicators.”

“If you feel most alert, coordinated, and energetic at a certain time of day, that is likely your optimal training window. Morning exercisers often benefit from improved adherence and metabolic consistency, while late afternoon or early evening sessions may allow for peak strength, power, and coordination due to higher body temperature and nervous system readiness.”

– Mark Kovacs, PhD

However, he emphasized that: “Ultimately, consistency trumps perfection. The ideal time is when you can train regularly, safely, and with quality effort.”

“It’s important to differentiate between true fatigue and perceived low motivation,” Kovacs pointed out.

Still, he said that the trick is in understanding that “lower-effort” activities are still beneficial.

In fact, Kovacs noted, in many cases, starting with low-intensity movement can actually improve energy levels through increased blood flow and neurochemical responses.”

“A practical strategy is to reduce the barrier to entry,” he suggested. “Instead of committing to a full workout, start with 5 to 10 minutes of light activity [such as] walking, mobility work, or simple bodyweight exercises. In many cases, that initial movement leads to completing a longer session.”

“From a physiological perspective,” Kovacs advised, “low- to moderate-intensity exercise can enhance mitochondrial function and improve overall energy availability over time.”

This is important because mitochondria are the so-called powerhouses of the cell — they generate the energy that keeps our cells in good order, so boosting mitochondria ultimately leads to better cellular function overall.

“However,” Kovacs cautioned, “if fatigue is persistent, it’s critical to evaluate sleep, nutrition, hydration, and overall training load. Chronic fatigue is often a signal that recovery strategies need to be improved, not overridden.”

According to Kovacs: “Motivation is often misunderstood. It’s not something you wait for — it’s something you build through structure and habit.”

So if you are struggling to stay motivated to keep up with your exercise routine, he said:

“The most effective approach is to create a system rather than relying on willpower. This includes scheduling exercise at a consistent time, setting realistic and measurable goals, and tracking progress. Small wins compound over time and reinforce adherence.”

“Another key factor is variety and purpose,” he added. “Incorporating different types of movement — [such as] strength training, cardiovascular work, and mobility — can keep the routine engaging while also improving overall physical capacity.”

And when you’re really struggling, call on a friend, Kovacs advised: “Social accountability, whether through a training partner, coach, or group setting, is also one of the most powerful adherence tools we see in both athletes and the general population.”

“Finally,” he said “it’s important to connect exercise to a bigger purpose; whether that’s improving healthspan, maintaining independence as you age, or performing better in daily life. When exercise has meaning, consistency follows.”

Even with structure, motivation, and a strong sense of purpose, life can still get in the way sometimes, and people may find themselves skipping exercise for a day or two.

That is not an issue, Kovacs said. In fact, according to him, taking occasional breaks from one’s exercise routine “is often beneficial.”

“Adaptation — the process of getting stronger, fitter, and more resilient — occurs during recovery, not just during training,” he explained.

“For most individuals, especially as they age, incorporating at least one to two recovery or lower-intensity days per week is critical for long-term progress and injury prevention,” noted Kovacs. “That said, not every day needs to be completely sedentary.”

“Active recovery, such as walking, light mobility work, or low-intensity cycling, can support circulation and recovery without adding excessive stress,” he advised.

“The goal is not to train maximally every day, but to train intelligently and sustainably over time. That’s what ultimately drives both performance and longevity,” stressed Kovacs