Working out twice a day, sometimes called “doubles” or “two-a-days,” can mean anything from running twice a day to running every morning and strength training in the evening to doing a yoga class at lunch and a cardio or strength workout at night, and anything in between. In a nutshell, it simply means you perform two bouts of exercise, either of the same or different types, within the same day but separated by a period of time.
While doubles can be a powerful tool to enhance performance, it’s important to approach them strategically to avoid overtraining or burnout.
Should You Work Out Twice A Day?
In general, doing doubles can be healthy and beneficial for your progress. Still, there are also scenarios in which two-a-days are counterproductive, if not a definitive net negative on your body. The differences lie in the specifics of your workout sessions and overall health and fitness goals.
Benefits of Two-a-Day Workouts
Depending on the type, intensity and duration of your workouts, working out twice a day can double down on many of the positive benefits of exercise.
- Promotes Overall Health
Any minutes you accrue being physically active with your daily workouts can contribute to positive benefits such as reduced blood pressure, improved cardiovascular health, lowered blood lipids, regulated blood sugar, and reduced risk of several lifestyle diseases. - Enables Increase in Training Volume
The benefits of two-a-days are likely amplified if you can fit in a 45-minute workout in the morning and a 30-minute workout in the evening rather than just a single 60–minute workout in the morning. This results in a total of 75 minutes of exercise. - Improves Strength and Endurance
Studies have shown that doubles can lead to greater improvements in muscle strength and size due to enhanced muscle protein synthesis, fat oxidation, mitochondrial development, and power output. It can also cause favourable metabolic adaptations that contribute to glycogen sparing, leading to improvements in aerobic endurance. This bodes well for distance runners looking to stave off the dreaded bonk around miles 20 to 24 of the marathon. - Boosts Mental Health
Exercise produces endorphins, which elevate one’s mood and provide a sense of well-being. Low and moderate-intensity exercise also lowers cortisol levels, helping your body and mind feel less stressed. Exercise can also improve your focus and energy, so training twice a day can give you a double boost of feel-good chemicals, reduce pent-up stress, and help your brain feel sharp. - Helps You Fit It All In
Many people have inflexible schedules and don’t have enough time to fit longer sessions in their workout plan. For example, if you want to run five days a week and weight lift three times a week, you need to fit in both on at least one day. You can do your threshold run in the morning then head to the gym for a warm-up and strength training before dinner. Working out twice a day allows for a mental and physical reset before hitting your second workout. Try to leave an ideal six-hour rest window between workouts for maximum results.
Drawbacks of Two-a-Day Workouts
There is the risk of overtraining, injury, and mental and physical burnout, particularly if you are increasing your training volume. Moreover, working out twice a day reduces the time your body has to rest between bouts of physical exertion and stress.
Doubles can also increase cortisol levels, which can suppress the immune system, impact appetite, and disrupt sleep patterns. The greater the intensity and duration of your workouts, the more cortisol they will increase.
Lastly, working out twice a day can be mentally taxing as it takes up more time and energy in the day, whether from the additional minutes of exercising, or commuting to and from a workout location.
Essential Tips for Successfully Working Out Twice a Day
If you want to add doubles to your training plan, the goal needs to be capitalizing on the benefits while mitigating the potential risks.
- Don’t Do Two-a-Days Every Day
Limiting the number of days you exercise twice will give your body ample recovery time. Similarly, if you are a beginner and just started to add two workouts in one day, gradually increase the frequency, duration, and intensity of the secondary workouts over time.
For example, add an easy 15-minute shake-out ride on an indoor cycle in the evening on the days you have a higher intensity threshold run or interval session in the morning, and progress to 30 minutes after a couple of weeks. - Pair Smartly
To reduce the risk of injury and maximize fitness gains, double up with two very different forms of physical activity, such as high-impact cardio with strength or strength with flexibility or speed/power with low-impact cardio. Where possible, try to choose exercises that use different muscle groups. For example, if you cycle in the morning, do upper-body and core-strength training exercises rather than a lower-body workout. - Be Mindful of Intensity
Going full blast for both workouts can be overtaxing, so mix up the intensity of your doubles so that at least one workout is more of an active recovery in terms of modality (yoga, walking, or deep-water walking) or effort level. Two intense workouts in one day may be just too much. - Prioritize Your Primary Workout
Make your harder workout your first workout of the day. If you want to run and lift weights and your running workout is your priority, run in the morning and save the lifting for later in the day to avoid running on tired muscles. - Monitor Your Heart Rate
Your resting heart rate can provide a window into how well you’re recovering from workouts. If you notice your heart rate upon waking to be trending upward, it’s a sign you need to cut back and give your body more recovery time. - Keep a Fitness Log
Record all your workouts, including subjective data on how you feel, to help stay on top of niggles and signs of overtraining. - Rest
Honour the rest day and ensure you get a full rest day weekly or at least every other week. - Fuel Like a Pro
Fuel your body with the same desire for excellence. Focus on whole, unprocessed foods, and ensure your caloric and nutrient needs are met to keep your body healthy. Carbohydrates are key to high-intensity workouts such as running, HIIT, and just about any form of cardio. But be sure to get all your macros in (carbs, proteins, and healthy fats). Also, keep your hydration in check. - Listen to Your Body
Modify your training schedule accordingly. The goal of working out is to improve your health and fitness, not detract from your health or quality of life.
If you are going to give those doubles a try have someone help you organize your training sessions, like a coach or personal trainer, to make sure you are being safe and maximizing your gains.
This article is edited for length and reprinted with permission from Marathon Handbook – www.marathonhandbook.com.
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