Mental or Physical Exhaustion: Assessing Your Energy

A Marine cools down during a break in his unit's 10-mile forced march held aboard Camp Lejeune, N.C.
A Marine with 2nd Maintenance Battalion, 2nd Marine Logistics Group cools down during a break in the unit's 10-mile forced march held aboard Camp Lejeune, N.C., May 29, 2013. The four-hour hike challenged each of the unit's service members' endurance and will power to continue through physical and mental exhaustion. (Lance Cpl. Sullivan Laramie/U.S. Marine Corps photo)

Every stage of life has a way of adding stress (both mentally and physically) that can exhaust us sometimes. Learning to assess why you are feeling tired quickly and learning coping mechanisms to prevent serious fatigue is key to your happiness, productivity and general usefulness. Quickly assessing that you are more mentally fatigued than physically tired and have the discipline still to do something physical is critical to preventing burnout or chronic stress symptoms such as:

  • Irritability
  • Body aches and soreness
  • Lack of focus
  • Loss of motivation to work, play, exercise and eat well
  • Illness
  • And more than 50 others listed at

I often say, sometimes life gets in the way of a scheduled workout plan.  Some days are meant to be taken as a rest day while some require you to burn off daily stresses physically. The more you get into the habit of recognizing and overcoming this type of fatigue, the easier it is to do something to metabolize that stress in a healthful manner.

Mental and Physical Stress — Same Stress Hormonally but ...

Working a long day at a desk, in an office or school, with multiple projects due is tiring and stressful. But it is different than a long day of physical labor.  Both can be equally tiring, but to fight off the long-term effects of stress, you need to do something physical if you are more mentally stressed. If you are more physically tired, then you need to do a light stretch to loosen sore muscles and relax. Breathing deep, eating well, hydrating and getting a good night's sleep are all part of you being a better handler of stress today, regardless of the type.

Think of handling stress as how we have evolved as a species. Stress in early human life focused on finding food and shelter, surviving and escaping attacks from animals, and other humans wanting your food and shelter. Stress also can be dealt with as a natural fight-or-flight response. Deal with it now before it becomes psychological and chronic to your health.

Consider Today's Human 

An example of a fight-or-flight response today for us is a resistance workout and an elliptical machine. Of course there are many more ways to "fight or flight" such as calisthenics, martial arts and running -- probably the most primal of all stress relievers we have today if you think about it. 

For the laborer who is physically tired, there is nothing wrong with you working out in the gym, but you should balance it with something cardiovascular, too -- just to breathe deep and pump some oxygen through your system. This can help relax you as long as you are smart about not adding more physical stress to your day by overdoing it in the weight room, too. 

Constant physical stress is not good, either. As you age and increase your responsibilities (home and family stresses), you will find that a physically stressful day of work, plus additional hardcore weight training, will require careful consideration with perfect recovery to avoid overtraining syndrome. Call it overtraining or lack of recovery; it exists.

Stress Is a Killer, Literally

Constant physical, mental and emotional stress can lead to an early death with many of these symptoms (from

  • Mental-health problems, such as depression, anxiety and personality disorders
  • Cardiovascular disease, including heart disease, high blood pressure, abnormal heart rhythms, heart attacks and stroke
  • Diabetes
  • Menstrual problems and sexual dysfunction, such as impotence and loss of sexual desire in men and women
  • Loss of muscle mass, increase of fat production, obesity
  • Skin and hair problems such as acne, psoriasis and eczema, and permanent hair loss
  • Gastrointestinal problems, such as acid reflux, gastritis, ulcerative colitis and irritable colon

A Simple Way to Assess if You Are Mentally or Physically Exhausted

Have some internal awareness. Take a minute and think about your day. 

What have you done physically already? On your feet all day? Ran in the morning?

Have you eaten well? Hydrated properly? Do you need electrolytes (if sweaty during the day)?

Do a body scan from head to toe. Do you have any aches or pains?

If you are "tired" from sitting all day, do something physical. Burn off that stress and get some needed exercise. Anything will suffice, even for 15-20 minutes.

If you are tired, achy or sore at the end of the work day, you may want to do some light cardio and stretch to feel better. If you are low on energy, it could be simply from dehydration and lack of replenishing electrolytes. It also could be that you have not eaten anything in several hours. Here are some quick food energy ideas.


After a long, mentally stressful workday, understand that you are not physically exhausted. You still have something left in the tank, and burning off that stress in the form of some physical activity is the way to go. Follow it with deep breathing cardio or stretching to relax.

After a long physical day, do some light cardio, stretch, eat well, walk the dog and relax at a minimum. 

Naturally, these recommendations all depend on your age, current physical capabilities, your daily stress levels and time. When absolutely short on time, take a shower and let the water hit your head for an extra five minutes. Think of nothing, breathing deeply as a quick relaxation tool. Then, stretch lightly while you wind down for the evening. That is going to help you far more than doing nothing, overeating, overdrinking (alcohol) and watching TV all night.

Stew Smith is a former Navy SEAL and fitness author certified as a Strength and Conditioning Specialist (CSCS) with the National Strength and Conditioning Association. Visit his Fitness eBook store if you're looking to start a workout program to create a healthy lifestyle. Send your fitness questions to

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