Pushing the boundaries: the hidden sleep penalty

The mantra ‘no pain, no gain’ is commonly used by athletes during hard periods of training. Of course, those among you who are experienced sportsmen or women will know that experiencing actual pain during a training session is more often than not a bad thing, and what is really meant is ‘no effort, no gain!

Producing training adaptations

For any athlete in training, there are three possible routes forward regarding fitness levels: gaining fitness, static levels of fitness or a decline in fitness. In the initial stages of training as a novice athlete, gaining fitness occurs almost by default, since even light or sporadic training will produce more of a training stimulus compared to zero training! However, as time progresses, fitness levels advance, and a solid training base is built up over a few months, athletes need to plan and execute their training more thoughtfully. Just simply carrying on with the training that ‘got you there’ will no longer be sufficient to gain fitness – ie fitness levels will become static because the training stimulus to produce further adaptations is no longer sufficient.

There are many ways to produce further training adaptations and fitness gains, including the introduction of, or stepping up of high intensity workouts (such as interval sessions, race-pace training etc), and/or training volume increases. Athletes can also incorporate other training modes such as strength training, flexibility work etc, which while not essential for the athlete’s main sport, are able to build the resilience needed to help support a heavier training load. Of course, higher training volumes and intensities, plus the inclusion of other modes of training means that athletes need to start paying extra attention to recovery, and planning their programs more carefully with this in mind.

Overreaching

In a well-designed training program, there will be blocks of higher-intensity or duration training interspersed with periods of lower-intensity training (including plenty of rest days) to ensure there are sufficient periods for recovery and rejuvenation – sometimes referred to as block training (see this article by Owen Anderson). During these relative recovery periods, the process of ‘super-compensation’ occurs, leading to a subsequent improvement in performance (figure 1).

As SPB author Alan Wells describes in his article on structuring soccer training programs, the transient state of fatigue that is induced during the blocks of higher-intensity/duration is termed as ‘functional ‘overreaching’, and can be a favourable condition for athletes with good existing levels of base fitness to experience if they are to gain performance improvements⁽¹⁾. In functional overreaching, a temporary state of fatigue is deliberately induced by planned higher-than-normal training loads, which when combined with enough subsequent rest and recovery, leads to useful gains in fitness.

While functional overreaching can be a very desirable outcome in a well-constructed training program, another type of overreaching known as ‘non-functional overreaching‘ is most definitely not. In non-functional overreaching, an unwanted state of fatigue is induced. This can happen for various reasons⁽²⁾:

·        A poorly planned training program with excessively high-load periods.

·        A program that doesn’t include sufficient recovery days.

·        In team and field sport athletes, when extra matches or games are scheduled in at short notice.

·        When athletes undertake physically demanding tasks during their leisure time (eg building or construction work).

·        When athletes experience psychological stresses not connected with training environment, such as exams, financial worries, moving house, relationship difficulties.

·        Poor nutritional and sleep behaviours.

As a rule of thumb, we can say that non-functional overreaching has occurred if the planned overreaching does not result in a performance improvement after a short rest, or causes more short term performance decline than planned.

Figure 1: How differing training pathways can lead to performance enhancement or overtraining