Image: Another long night ahead in the Southern Pacific

Text by Eduardo Rosa for Global Solo Challenge

Fatigue Management, Cognitive Performance and Emotional Strains in Solo Offshore Racing

There is a fundamentally different element in solo offshore sailboat racing compared to ‘just’ sailing alone across the ocean; fatigue management. In order to cope with the exceptional strain that 24-hours-a-day readiness to perform imposes during single-handed sailing over many days, competitive sailors adopt polyphasic sleep patterns – or naps, lasting even just a few minutes at a time. A polyphasic sleep regime only partially counterbalances the loss of sleep.  Click here to read more about this topic in a previous article by Marco Nannini

 

 In this article, our focus is the cognitive and emotional strains that several physical and psychological stressors – such as sleep loss, circadian misalignment, and workload – will have on single-handed round the world competitive sailors and what this means in relation to fatigue management and performance.

Speed and pace are the only words a solo racer hears in her mind. Extended consecutive work periods, insufficient recovery time, night work during circadian low, inconsistent work schedules and time-zone changes are now part of life onboard. Fatigue will invariably hit before they know it.
 

Mental and physical fatigue have cumulative adverse effects on functional performance. These include vigilance decrements, increased lapses of attention, cognitive slowing, short-term memory failures, and decision-making disturbances. Sleep restriction to 4-6 hours per day leads to a ‘sleep debt’ that impairs performance within a week. By this time, approximately, sailors can really feel the impact of fatigue on themselves and, not unlikely, on their performance and possibly their safety.

In several scientific studies addressing fatigue, even high-performance trained professionals such as civil and military pilots, fatigue implies that accuracy and timing degrade, lower performance standards unconsciously become acceptable, multi-tasking becomes difficult. Even simple, well-practice activities require more effort, the ability to integrate information is lost, attitude and mood deteriorate, and situation awareness declines.

Even before reaching a state of sleep deprivation, reaction times degrade after 7 hours of prolonged activity in tasks that require fast responses.

Fatigue impairs cognition
Emotions are similarly affected. As fatigue impairs cognition, it also alter emotional states and the capacity to regulate bad moods. In other words, when people are happy and rested, they tend to make positive evaluations of a situation, and build their actions accordingly.

On the other hand, when constant fatigue has already set in for the solo sailor, exhaustion of mental and physical resources may become more severe. Especially when conditions require further physical and/or psychological effort, leading to a state of exhaustion. Consequently, mood is affected, and so is the capacity to perform. When racing single-handed, mood and the cognitive level of the sailor at any given moment influence the course of the competition.

 

These functional impairments are not well managed by most solo sailors. Does this mean that when fatigue hits, there is nothing one can do about it? Although functional and emotional impairments will occur, research shows that it is possible to counteract its effects to some extent. Much will depend on specific situation, the person, cognitive and emotional resources and prevailing conditions. Coping with the extreme demands of solo racing requires significant mental effort. Understanding how to better deal in such demanding situations can significantly help.

One of the regulatory cognitive control processes relates to motivation (see figure below), and most solo sailors already have this tool in their toolbox. When you suffer from extreme fatigue for prolonged time, intentional actions are impaired. In these circumstances, neo-cortical sensory and motor systems (and various sub-cortical structures) send the message that you should stop and rest (unintentional inputs). However, the prefrontal cortex – the primary area of the brain behind your forehead responsible for controlled processes – can override such systems. When this happens, motivation is actively helping in maintaining or recovering task performance.

Going that ‘extra mile’
Going that ‘extra mile’, or ‘taking energy out of the blue’ that we have seen in athletes in the last meters of a marathon to overtake a competitor is due to the prefrontal cortex mechanism (controlled process) overriding (bottom-up) sensory inputs telling to stop. Emotion regulation is also somewhat subjected to this push-and-pull sensory inputs/prefrontal cortex control mechanism. This will be a constant in the life of the solo sailor during a race around the world.

It is important to notice that this does not mean that those suffering from extreme fatigue will always be able to counter its effects with motivation. To what extent is possible to minimise fatigue effects with will power depends on the availability of physical and mental resources at that exact moment as well as individual differences in coping with environmental demands.

Giving all you have…
 
How can the solo sailor help himself in coping with fatigue, and how could he improve the success of the prefrontal cortex in sustaining motivation to override sensory inputs indicating extreme fatigue? A common approach to avoid fatigue-related problems is to limit time-on-task and duty time.

Incident and accident nearly double when a work shift extend from 8 to 12 hours with no break. For that, rest breaks during the day can help maintaining or even improve performance when fatigue from sleep loss and time-on-task occurs. Research shows positive effects of 5-20 minutes breaks on performance and alertness even when people are sleep deprived. And a break means a real break; one should aim at closing his eyes whenever conditions allow or even taking a short nap at any time during the day (look at the polyphasic sleep regime article again). The nap before a night watch, for instance, should be as long as possible to produce the greatest performance boost. Research also shows that a 40-minutes nap can improve psychomotor performance and reduce the number of micro-sleeps in several operational conditions. Additionally, the nap should follow the circadian phase whenever possible.

Do not miss the sleep train
This means that nap timing is best when it is easier to fall asleep and when the quality of sleep follows the body’s internal clock. The readiness to fall asleep is highest when core body temperature is low (pre-dawn and early morning hours) and diminished when core body temperature is highest (early evening hours). Finally, certain short meditation practices (10 minutes practices, 3 times a week), such as Brief Mindfulness-Based-Training, may also contribute to reduce mental fatigue (the latter is a huge topic to be expanded at the next opportunity).
 

Sailors have raced around the globe and have been through the extreme conditions of solo offshore races. Cognitive and emotional resources are not to be underestimated in such environment, and fatigue management strategies can considerably aid in regulating cognitive control processes, emotions and emotion regulation, performance and, most importantly, safety. A proper training and consideration of fatigue mitigating strategies can also enhance the chances of crossing the finish line first and in well-balanced mental and physical conditions.

References
Boksem, M. A., & Tops, M. (2008). Mental fatigue: costs and benefits. Brain research reviews, 59(1), 125-139.

Caldwell, J. A., Caldwell, J. L., & Schmidt, R. M. (2008). Alertness management strategies for operational contexts. Sleep medicine reviews, 12(4), 257-273.

Frenda, S. J., & Fenn, K. M. (2016). Sleep less, think worse: the effect of sleep deprivation on working memory. Journal of Applied Research in Memory and Cognition, 5(4), 463-469.

Grillon, C., Quispe-Escudero, D., Mathur, A., & Ernst, M. (2015). Mental fatigue impairs emotion regulation. Emotion, 15(3), 383.

Hurdiel, R., Monaca, C., Mauvieux, B., Mccauley, P., Pa Van Dongen, H., & Theunynck, D. (2012). Field study of sleep and functional impairments in solo sailing races. Sleep and Biological Rhythms, 10(4), 270-277.

Hurdiel, R., Van Dongen, H. P., Aron, C., McCauley, P., Jacolot, L., & Theunynck, D. (2014). Sleep restriction and degraded reaction-time performance in Figaro solo sailing races. Journal of sports sciences, 32(2), 172-174.

Rosa, E., Gronkvist, M., Kolegard, R., Dahlstrom, N., Knez, I., Ljung, R., & Willander, J. (2021). Fatigue, Emotion, and Cognitive Performance in Simulated Long-Duration, Single-Piloted Flight Missions. Aerospace medicine and human performance, 92(9), 710-719.

Sarter, M., Gehring, W. J., & Kozak, R. (2006). More attention must be paid: the neurobiology of attentional effort. Brain research reviews, 51(2), 145-160.

Going the extra mile…

About the author
Eduardo Rosa, Ph.D., is a Neurocognitive Scientist and Human Factors Specialist. His research focus on the analysis of human performance in complex environments. He has been actively working with commercial and military pilots, particularly in quantitative and qualitative research in applied settings for enhancing human-machine interaction, improving overall safety and performance. He is also a competitive and offshore sailor, having participated in regattas in many different classes – such as Formula18’s – and completed many passages around the world.