Where does fatigue come from?

It doesn’t come from the body. Even when people exercise to exhaustion, studies have shown that there is fuel left in the tank – one found there was enough energy left in muscle tissue for participants to have kept going for another seven or eight minutes. The brain puts the brakes on, stepping in to stop us from over-exerting and injuring ourselves long before we reach our actual limits.

According to the latest research, our physical endurance is determined by our “perception of effort” – how much work the brain thinks that the body has done. But the brain can be tricked. In Brazil, a group of scientists improved power output in cyclists by 10% by running a small electric current through the brain. Elsewhere, it has been shown that giving athletes incorrect information about the temperature can help them maintain their performance in hot conditions, and that lying to them about their split times can help them break personal bests.

In one study, Professor Samuele Marcora and colleagues asked people to pedal an exercise bike at a fixed pace for as long as possible. Unbeknown to the participants, a screen in front of them was flashing up subliminal images for 1/16th of a second at a time. Cyclists flashed images of sad faces rode for 22 minutes and 22 seconds on average. Those shown happy faces reported less perceived exertion, and rode for three minutes longer. Marcora now wants to develop a pair of goggles that could flash up this kind of image at athletes while they are out training.

Forcing ourselves to keep going also means ignoring all the signals from our body telling us to stop. This “response inhibition” is very mentally taxing, and it causes a substance called adenosine to build up in the brain. Adenosine is associated with the feeling of mental fatigue – it builds up when people run marathons or work on boring spreadsheets, or if they haven’t had enough sleep. Adenosine increases perception of effort. It is the enemy of endurance.

Mo Farah drinks a couple of espressos before a race, to reduce mental fatigue.

Caffeine blocks adenosine. This is why Mo Farah drinks a couple of espressos before a race, and why caffeine pills and gum have become an essential part of the long-distance runner’s pre-race preparation. You can also train your brain, by doing monotonous response- inhibition tasks before or during exercise. In the short term, this will make your performance worse, but in the long run your brain will learn to produce less adenosine, which will reduce perception of effort and increase endurance.

In one study, Marcora asked two groups of soldiers to do a time-to-exhaustion test, where they were asked to ride at a fixed percentage of their maximum until they couldn’t any more. After 12 weeks of training the control group’s time-to-exhaustion had improved by 42%. The other group performed a mentally fatiguing task alongside their physical training sessions. Their time to exhaustion improved by 115%.

Auditory versions of these tasks for smartphones are in the works, but you can replicate the effect simply by changing your training patterns. For your brain, running five miles after a hard day’s work feels like the last five miles of a much longer run. It offers a much better workout for your willpower. It’s mind over matter, and fortunately for athletes – from the elite to the amateur – the mind is much easier to manipulate.

This article was originally posted at The Guardian.

Photo credits: occoquanbayperformance.com

About the author

Amit Katwala is the author of The Athletic Brain out on 11 August. To order a copy, go to bookshop.theguardian.com.

Back in the 80s I started studying psychiatry at the University of Illinois at Chicago. By the early 90s I had my very own practice (albeit small), again in Chicago. It was during these early days that I had a client – who shall remain nameless for obvious reasons – ask about subliminal therapy; they were very keen to try it. Up until that point I had used a combination of talk therapy (and medication where necessary) as is standard practice. I wasn’t familiar with subliminal therapy whatsoever, so I told my client I would look into it.

Now this was the very early 90s, so research involved several trips to the library. I’ve always been fascinated by the human mind so, while the hours spent in that library were long, they seemed to whiz by in the blink of an eye. Scientific evidence was (and unfortunately still is) sketchy on either side of the fence for subliminal therapy but I found enough evidence – as well as techniques – that I felt, if my client wanted to try it, I could, in good consciousness treat them in this manner.

Without going into the details of the case, I was very impressed by the results. I had used a combination of audio and visual subliminal therapy that I have (I’d like to think) improved upon since but the results were certainly worth paying attention to. However one client does not solid proof make. It also weighed on my mind that the possibility of the “placebo effect”, in this case, was rather high.

The very same client I had treated successfully with subliminal therapy then sent a friend of theirs to visit me. Over the course of four weekly visits, I treated them and was again extremely happy with the results. Not only was the treatment successfully but it was certainly much more quickly effective than talk therapy (more on this later).

Now I felt like my experience with subliminal therapy had a little more momentum behind it. When clients would come to visit my for their initial consultation, I would bring up the possibility of using subliminal therapy – explaining the positive benefits it could whilst also explaining that there was very little in the way of scientific research in the field. Most were more comfortable with traditional therapy, which is perfectly understandable, however, around ten to twenty percent were willing to try subliminal therapy.

I’m not going to lie and say it was a complete success every time, but in comparing what I consider a success rate (the client feeling they no longer need to see me, independently at peace with the issue they came to see me about) – there could be no doubt. Subliminal therapy was working and working well.

I still remember those early years very clearly. Amongst my clients – particularly those used opted to use subliminal therapy in conjunction with traditional methods – I was getting a lot more referrals than practising psychiatrists I’d gone to school with. Ever since I has always offered subliminal therapy at my practice. Some traditionalists scoff at such a “new age” method with the lack of empirical evidence but I have often wondered if such methods are held back because they aren’t as financially lucrative as the old talk therapy plus medication method. To some, while they do care about their clients, money is certainly a factor; why treat someone in two months when you can treat them in two years?

I am proud to call myself a psychiatrist and subliminal therapist and I’d like to see more psychiatrists – and others in the mental health field – embrace more techniques such as subliminal therapy, meditation, hypnotherapy, etc. The mind is such a complex thing that rarely can one angle of attack solve a problem completely. A complex issue often requires a complex solution.

Think about your life experience. Have you ever had a talk with a friend when you’ve needed to get something off your chest? It feels great to have the weight off your chest but that release of pressure generally only lasts until the next morning or the next time you are confronted by that problem.

What I am saying – in a round about way – is that the mental health practice in general needs a shake up. It needs to start looking into new ideas and also looking into the combined effect of techniques.

I hope this article has made you think a little about subliminal therapy, the mind, and mental health. The way to growth is trying new things and moving forward. If you can keep that thought in your mind, your life will greatly improve.

About the author

Dr. Jack Crosby has recently opened his own website, SubliminalMP3Downloads.com, to allow people from around the world to sample his subliminal therapy techniques.

The subliminal aspects of everything that happens to us may seem to play very little part in our daily lives. But they are the almost invisible roots of our conscious thoughts.

~ Carl Jung

The human mind is divided in two parts, the conscious and the subconscious mind. The conscious mind works while we are awake and conscious. The subconscious on the other hand, is always activated, regulates everything in our body, our character, our speech, and receives and processes information, no matter what we do.

Think of your mind as an iceberg. The conscious part is the tip of the iceberg that you see on the surface of the sea, say 5% of the total part of the iceberg, while the remaining part under the sea is the subconscious. Just think how powerful it is.

Another simple way to describe it is to see it as a tape player, which plays continuously tapes” which installed throughout the course of our life feelings, thoughts, patterns. The subconscious mind receives information for which we are not aware of and stores them. If we receive information in an appropriate manner and at a high volume and frequency, then the information dwell in the mind and become an important part of who we are. This is why many “gurus” and lovers of self-help and personal development, point out and want to have access to the power of the subconscious. Because, if you put in it another tape”, then the result will be different. The train of thought changes, making us work differently, and so, inevitably results are different. Dr. Joseph Murphy says in his book The Power Of The Subconscious, “change your thoughts and you change your destiny” [1].

How Do Subliminal Messages Work?

Subliminal messages are messages (phrases and images) that operate below the level of conscious awareness and delivered in a way to be perceived from the subconscious mind. They may be audio subliminal messages and of course, visual.

For example, we can take the phrase “I am confident” and embed it into a music track where the conscious mind will not hear it clearly or in a video in which will be displayed for a split second, so the conscious mind will not have enough time to process it logically. In both cases, the phrase is clearly perceivable from the subconscious mind.

The constant repetition of this phrase or others helps on rewiring (creating new neural pathways) long thought patterns and one to think more positively, lose weight, have more confidence etc.

The subliminal messages technology exists for several decades. Many studies have shown that they can produce satisfying and lasting effects, from breaking unwanted habbits to improving performance. This technology is successful because offers the capability to interfere the “guard” of the subconscious mind, namely the analysis and processing of the logical, conscious mind.

The Science and How They Affect Us

There have been several surveys and studies that prove the effectiveness of subliminal messages technology.

  • Martijn Veltkamp (PhD-student), demonstrated that you can motivate people to do things that already had the intention to do them, using visual subliminal stimuli [2]
  • According to Professor Benjamin B. Wolman, author of more than 40 books on psychology, conscious thought can be influenced by stimuli outside of conscious awareness. He adds, with reference to Silverman (1967), that Freud’s study of consciousness “assumes that a subliminal input raises the activation level of existing unconscious motives” [3]
  • Dr. Norman Dixon, a psychologist at University College London, has done extensive research on subliminal learning. In his scholarly work Preconscious Processing he cites 748 references to studies on the effects of subliminal communication, with over 80% showing positive results [4]
  • Dr. Eldon Taylor, director of Progressive Awareness Research and a Fellow in the American Psychotherapy Association, firmly believes that subliminal information when presented in an appropriate manner, is processed, retained, and acted upon [5]
  • The research of Dr. H Bahador Bahrami, a neuroscientist at the University College of London, using brain scanners showed that the brain absorbs subliminal messages when not too busy [6]

Several studies have focused on the possibility of using subliminal messages to produce specific results:

Academic Performance

An article in the Journal of Counseling Psychology (Journal of Counseling Psychology) [7], reports a study by Dr. Kenneth Parker, a psychologist at Queens College in New York. Dr. Kenneth Parker conducted a study to determine whether subliminal messages can improve academic performance. Careful statistical analysis of the effects of subliminal stimulation, showed significant improvement in academic performance of students.

Weight Loss

Two groups of overweight women participated in a course for weight loss, where one group received audio subliminal suggestions, while the other group weren’t. The women of the group that had exposed to subliminal suggestions lost more weight, while the difference in weight continued to increase during the follow-up [8].

Stop smoking

Psychologist Dr. Lloyd H. Silverman of New York University, has studied more than 40 groups of smokers. Half of each group were exposed to subliminal audio messages, and the other half not. Within a month, 66% of people exposed to subliminal messages stopped smoking, compared with 13% of others. This led Silverman to conclude that subliminal messages make it four times more likely someone to be able quit someone smoking [9].

It is obvious the fact that subliminal messages have the potential to affect us and become part of our beliefs. They are a useful and powerful tool to change oneself. The applications can be infinite, from eliminating phobias and anxiety to increasing self-confidence, self-esteem and other mental abilities.

Here’s one video about removing subconscious blockages, that uses both visual and audio subliminals:



  1. Murphy, Joseph. The Power of Your Subconscious Mind. Wilder Publications, November 2008.
  2. http://www.sciencedaily.com/releases/2009/06/090630163523.htm
  3. Wolman, Benjamin B. Handbook of General Psychology. Prentice Hall; 1st Edition, June 1973.
  4. Dixon, N. Preconscious Processing. John Wiley & Sons, January 1982.
  5. Taylor, E. “Subliminal Information Theory Revisited: Casting Light on a Controversy”. Annals of the American Psychotherapy Association. (2007).
  6. http://www.theguardian.com/science/2007/mar/09/neuroscience.medicineandhealth
  7. Parker, Kenneth A., “Effects of Subliminal Symbolic Stimulation on Academic Performance.” Journal of Counseling Psychology, Vol. 29 (1), 1982.
  8. Silverman, L.H., Martin, A., Ungaro, R., and Mendelsohn, E. “Effect of Subliminal Stimulation of Symbiotic Fantasies on Behavior Modification Treatment of Obesity.” Clinical Psychology – http://psycnet.apa.org/psycinfo/1979-13876-001.
  9. Silverman, L.H. “Effects of Subliminal Stimulation of Symbiotic Merging Fantasies on Behavioral Treatment of Smokers.” The Journal of Nervous and Mental Disease.

More sources for further study: