The two main types of fatigue are physical and mental.
Physical fatigue relates to your performance of physical tasks, and will be influenced by the type and intensity of the activity, and your existing levels of fitness and strength.
Mental fatigue refers to a "tired" state of mind which may result from a lack of sleep, or pro-longed periods of demanding or repetitive cognitive tasks.
Both types of fatigue can make you exhausted and lethargic, and, unfortunately, can happily co-exist.
But from an exercise perspective, it's interesting to explore the impact of mental fatigue on your ability to perform physically. Just how does your mental state impact on your ability to exercise?
published in the Journal of Applied Physiology
compared the performances of cyclists who undertook different mental tasks prior to exercise.
Participants performed either a computerised task designed to trigger mental fatigue, or watched mind-numbing documentaries for 90 minutes, then exercised to exhaustion.
Each cyclist was tested for both protocols (the computerised task and the documentary watching) as part of the experiment, having two days rest in between.
The key finding was that time to exhaustion was significantly lower in subjects who were mentally fatigued, and that an aversion to further effort is a common feature of mental fatigue
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The study highlights the impact that mindset has on your ability to exercise. The researchers found that mental fatigue limits exercise tolerance by triggering a higher perception of effort.
This crucial role that perception plays in effort and fatigue is relevant to everyone who exercises.
- Is the level of effort you are putting into your workout where it should be, or do you just "think" you are working hard enough?
- Is your perception of effort, fatigue and pain holding you back?
If you feel like your results have plateaued, or are well below what you would reasonably expect, try these hacks to push your boundaries and win the battle with fatigue.
Exercise with others
Training in groups can help to gauge the level of effort others put into their exercise, and how you compare. This is not to say you need to be like anybody else, but it can be helpful to see what limits people place on themselves under fatigue.
Depending on your personality, some people tend to push themselves harder in a group environment, thriving on a little friendly competition
Introduce extra intensity (gradually)
Interval training is a great way to add small bursts of extra effort in measurable doses, interspersed with regular rest periods. A gradual approach is especially important if you are overweight, relatively untrained, or are recovering from injury
Embrace the burn
If you want to get super fit through cardiovascular exercise such as running, or add strength through weight training, you will have to experience what most people would perceive as a burn. There's no doubt you need to push yourself a little beyond your comfort zone to see noticeable results.
Some people even grow to enjoy this “burn”, knowing the benefits it brings. Muhammad Ali once said "I don't count my sit-ups - I only start counting when it starts hurting, when I feel pain, that's when I start counting, ‘cause that's when it really counts."
Know the line between the burn and pain
Exercise shouldn’t be too easy, but it also shouldn’t be too hard. Recognise there is a clear distinction between a burn, and pain. A burn is a feeling in your muscles or lungs where you are exercising reasonably hard, but within your capabilities.
On the other hand, pain in your joints, neck, back or elsewhere that limits your movement and feels uncomfortable should be seen as a warning sign. Don't push through chest pain or tightness, severe breathlessness, dizziness or light headedness
Schedule rest in your routine
If you train hard, it's important to schedule rest and recovery time. Prioritise sleep, and ensure there are lighter training days and rest days in your routine. This may help to prevent both physical and mental fatigue
Source: J Appl Physiol 106: 857–864, 2009 DOI: 10.1152/japplphysiol.91324.2008