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A brief introduction to unexplained underperformance syndrome (UUPS)

Also known as overtraining syndrome, literature has suggested to rename this persistent decline in athletic performance to ´unexplained underperformance syndrome (UUPS)´ due to the multiple systems that may be involved and it´s diagnosis complexity.

Unexplained underperformance syndrome

What is unexplained underperformance?

The term is used to describe a significant episode of underperformance with persistent fatigue, that is, maladaptation to any training (1).

Recognised signs & symptoms of unexplained underperformance:

It is important to note that UUPS usually involves a combination of multiple signs & symptoms. Symptoms are often representative of underlying hormonal, immunologic, neurologic and psychologic disturbances (4). However, having one or more of these signs & symptoms does not necessarily mean UUPS. Currently, more research is needed to better understand UUPS.

  • Lack of adaptation to training

  • General constant fatigue

  • Low mood

  • Imbalanced hormone levels

  • Loss of libido

  • Increased rate of percieved exertion (RPE) for usually easier training sessions (long-term)

  • Loss of competitive drive

  • Loss of appetite

  • Unexplained weight loss or gain

  • Unexplained chronic stiff & sore muscles

  • Poor sleep

Possible contributors of unexplained underperformance:

An imbalance between training load and recovery may not be the primary cause for UUPS (1). It is difficult to pinpoint exact causes making diagnosis difficult.

  • Too much high volume & intense training with too little recovery

  • Lack of nutrients in the diet

  • Insufficient carbohydrates to suit training and lifestyle

  • Constant mental/ emotional stress

  • Poor quality/ insufficient sleep

  • Taking on more than you can handle

  • Monotonous training

  • Lack of education

Possible solutions for prevention of unexplained underperformance:

It is always advised to take steps for prevention. Aim to include a prevention strategy that addresses nutritional, physical & psychological methods.

Here are a few examples:

  • Daily contact with an experienced trainer

  • Individualised nutrition plans suited to the athlete´s needs

  • Education for athletes on UUPS

  • Ensure daily nutrient-rich meals

  • Avoid nutrient deficiencies

  • Regular blood & performance testing

  • Focus on everyday recovery & relaxation methods

  • Ensure sufficient rest days

  • Minimise mental stress

  • Minimise exposure to toxins

  • Make sure to have ´me time´

  • Listen to your body

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1) Lewis, Nathan A; Collins, Dave; Pedlar, Charles R; Rogers, John P (2015). Can clinicians and scientists explain and prevent unexplained underperformance syndrome in elite athletes: an interdisciplinary perspective and 2016 update. BMJ Open Sport & Exercise Medicine, 1(1).

2) Budgett R, Newsholme E, Lehmann M, et al. (2000). Redefining the overtraining syndrome as the unexplained underperformance syndrome, British Journal of Sports Medicine. 34, 67-68.

3) Maughan, Ronald J. (2013). The Encyclopaedia of Sports Medicine (An IOC Medical Commission Publication) || Overreaching and Unexplained Underperformance Syndrome: Nutritional Interventions.10, 404–414.

4) Kreher J. B. (2016). Diagnosis and prevention of overtraining syndrome: an opinion on education strategies. Open access journal of sports medicine, 7, 115–122.

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