Our bodies function on the principle of working towards maximal efficiency. We are constantly adapting to the environmental stressors in our lives and our bodies are no different. Knowing this helps us to design optimal workouts that maximize our physiological improvements, and avoid those mushy middle workouts.
Mushy middle…what’s that?
Do you find yourself ending a workout breathless, but not exhausted? Glistening but not dripping with sweat? Tired, but could go for another 20 minutes? Starting the workout the next day fatigued and drained? Congratulations, you are a mush middle workout fiend. While the fat burning zone isn’t your friend for weight loss, a chronic mushy middle workout plan isn’t your friend for ANY goal.
Let’s jump back to some light physiology. The main component of exercise (aerobic is my focus for this for now, but some principles apply to anaerobic) is oxygen consumption and utilization. At rest, you breathe in, oxygenate blood, pump it to throughout the body, and breathe out the leftover CO2. During high intensity exercise, you push your body to a point where it can no longer take in enough oxygen to deliver enough oxygenated blood to the working muscles. With decreased oxygen, there’s an increase in acidic metabolites, which ultimately lead to your inability to continue exercising- there are a myriad of factors, but let’s just keep it at you can’t take in enough oxygen to feed the oxygen-starved muscles.
Last post I touched on fuel sources for exercise and how exercising at higher intensities leads to an increase in carb usage and working at lower intensities pulls more from fat stores. If your goal is to run faster, your body needs to be able to process the increase in oxygen demand that accompanies a faster pace. If your goal is to run longer, your body needs to become more efficient at utilizing fat as a fuel source.
So how does this look in a training program?
If you are just starting out the best way to train is at high intensities. You want to challenge your body by doing workouts that place a large demand for oxygen. These will be shorter workouts (20-30 mins), but they will be intense and exhausting and when you finish you should FEEL finished. If you complete the workout and think “I could do another ten minutes,” then you were not working out hard enough. An easy way to get a high-intensity workout is to do the HIIT training I’ve mentioned before. By doing 1 minute on, 1 minute off intervals, you are keeping your heart rate high throughout, but giving your body enough rest to be able to complete the workout. . This type of training pushes your oxygen consumption limits and forces your body to improve its efficiency (resulting in a higher VO2). Due to the high intensity of the workouts, to start out try and do this 2-3 days a week and have light/easy days for the others.
That last part is crucial. Make the days when you aren’t purposefully going high intensity light. These should be recovery days, and they are just as important as your intense days. Too many people make the mistake of going halfsies on their workouts and doing moderate intensity everyday of the week. Now, some exercise is better than NO exercise, but if you are working toward set goals, believe me when I tell you having a greater differentiation between your workouts is a MUST.
These easy days should be a low intensity and longer duration. Remember, their purpose is to keep you “working” while also getting you used to longer duration exercise. If you are training for a 5k, these “long trainings” aren’t as crucial because overall you are talking about an event that even if you walk you will finish in under an hour. So if a 5k is your goal, make the easy days the days that you go out and run a nice easy mile (continuous, but slow). If you are training for races of longer duration though, these “long easy” runs become crucial. The high intensity days should remain short and fast while the long slow days should be a decrease in pace with an increasing mileage (or distance).
I knocked the slow fat burning zone in my last post, but that was when our focus was weight loss. The bottom line is that the most important component of your workout is intensity. Your intensity should be aligned with your goals, and these mush middle moderate intensity workouts are one of the biggest obstacles for reaching performance and weight loss goals. So if you, like the vast majority of people, have fallen victim to the “mushy middle” workout, refocus on making your hard days truly HARD and your easy days really easy. The distinction of intensities for training may be just the boost you need to reach your next goal.