Exercise conundrum: When's the best time to work out?

When is the best time to exercise? It's a question people ask when striving to reach the recommended physical activity level. Whether you exercise in the morning, midday or evening, are there any physiological advantages to these times?

Supporters of either morning or evening workouts cite various benefits, including increased energy levels, enhanced performance and greater weight loss. Given the ongoing "When is the best time of day?" question, health experts have delved into the science behind exercise timing to shed light on the optimal approach for achieving fitness goals.

The case for morning workouts

For morning exercisers, the allure of starting the day with a workout is undeniable. Completing your workout before you begin your day can provide a sense of accomplishment. Add to that the post-workout release of endorphins, and your morning workout can serve as a powerful ego boost to set a positive tone for the rest of the day.

Morning workouts also eliminate the worry about finding time for exercise later in the day since it's often the only time of day that hasn't been committed yet to work, social events or family activities. This sense of freedom and flexibility can alleviate stress and help establish a consistent daily routine.

Strategically timed pre-exercise nutrition can significantly improve energy levels and performance for people embarking on morning workouts.

Starting the day with a balanced breakfast containing carbohydrates, protein and healthy fats can provide the necessary energy to power through a morning workout. Opt for whole-grain cereals and Greek yogurt with fruit, then allow sufficient time for digestion to prevent discomfort and maximize nutrient absorption.

If you're not hungry in the morning, try something simple like an energy bar or have a bedtime snack the night before your morning workout.

The case for evening workouts

Waking up early to exercise is the last thing you may feel like doing, so the case for evening workouts may be more appealing.

The body's ability to perform peaks in the afternoon and early evening for some people, with optimal muscle function, strength and endurance often occurring later in the day. That's because your body has had time to wake up by moving around throughout the day, you've eaten a meal or two to ensure adequate energy for your workout, and you may be more mentally alert.

In addition, oxygen uptake kinetics — your body's ability to take in oxygen and deliver it to the working tissues and the tissues' ability to use the oxygen — are more favorable in the evening, allowing for more efficient fuel use during exercise. That means your body is primed for performance in the late afternoon and early evening, making it an ideal window for high-intensity activities like interval training, strength workouts or speed work.

However, if you opt for evening workouts, you may face more challenges balancing your commitments, and physical and mental energy.

After a long day at work or shuttling around the kids all day, it can be hard to muster the motivation to go to the gym and exert a lot of physical effort. Intense physical activity in the evening also may trigger a stress response which can lead to difficulty falling asleep or cause you to wake up in the middle of the night if you experience cortisol disruption and release. If you're going to exercise right before sleep, consider a lower-intensity activity, such as a walk or lighter lifting session.

If you choose later-in-the-day workouts, ensure that you're getting adequate nutrients throughout the day so you have enough fuel available to support your workout. Eating a nutrient-rich meal within two hours after your workout can aid muscle recovery and help you better adapt to training. Consider options like grilled chicken with quinoa and vegetables or a protein-packed stir-fry to refuel and replenish after an evening workout.

What about a midday workout?

Whether working or at home, most people hit the dreaded afternoon slump around 3 p.m. A recent study of more than 90,000 people found that working out in the afternoon reduces the risk of heart disease or early death more than physical activity in either the morning or afternoon. The benefits of afternoon exercise for longevity were most pronounced for men and seniors.

Morning workouts may not be ideal for shift workers, those who work late or stay up late in the evening. A midday or early afternoon workout may allow for more sleep in the morning and extra time before your next evening shift or late night. 

According to a OnePoll survey, the most effective activity for people for an afternoon workout is going for a walk, which is a great way to improve both physical and mental energy.

The bottom line: Avoid the couch

For those who say, "I don't have any time to work out," here are tips for finding time:

• Schedule a "snack competing" activity. It's an excellent way to flip the script if you know you're apt to sit on the couch and snack in the evenings. Instead, use that time for a workout. You consume fewer calories by snacking less and also burn more calories with the workout.
• Split a workout into six, 10-minute sessions throughout the day. By day's end, you'll have exercised for 60 minutes.

Finding the right balance

No matter when you work out, if you're doing prolonged or intense exercise for more than 90 minutes, mid-workout nutrition can play a pivotal role in sustaining energy levels and preventing fatigue. Incorporate carbohydrate-rich snacks during extended workouts to maintain endurance and performance.

Ultimately, the best time to exercise is the time that fits into your schedule and aligns with your energy levels and preferences. Consistency and sticking to a regular exercise routine are far more critical than the time of day you choose to work out.

Experimenting with timing and being aware of how your body responds are essential in determining the best time to optimize your exercise performance, recovery and overall well-being.

Any time of day is better than no exercise in reducing the risk of death from any cause, including heart disease and cancer.

Next steps:

• Check out the ideas to get you moving any time of day.
• Find ways to fit a workout into your day.
• Learn how to calculate your target heart rate for exercise.
• Watch a video on heart health and wearable fitness device:

Andrew Jagim, Ph.D., is a sports medicine professional in La Crosse and Onalaska, Wisconsin. Jacob Erickson, D.O., practices sports medicine, and Alecia Gende, D.O., is a sports medicine and emergency medicine physician, both in Onalaska.