More energy in autumn with light, movement and good sleep

The days are getting shorter, the mornings stay dark for longer and daylight disappears again by late afternoon. For many people, autumn therefore feels not only cooler, but also more draining. Wanting more sleep, less exercise and an extra cup of coffee is not unusual.

Nevertheless, the idea that the body automatically switches into an energy-saving mode in autumn is too simple. Our bodies respond to changes in light conditions, but tiredness has many possible causes. Sleep, exercise, stress, diet and individual daily rhythms also play a role.

This is precisely why it is worth taking a closer look at what lies behind the typical autumn slump and which habits can actually help us feel more alert and capable in everyday life.

Contents

1. Why autumn can make you tired
2. Light sets the pace for our body clock
3. Why sleep becomes particularly important in autumn
4. Exercise works differently from what you might first think
5. Diet for stable energy in everyday life
6. Putting vitamin D in autumn into perspective
7. Coffee, alcohol and other energy drains
8. Small habits with a big impact
9. When tiredness is no longer just seasonal
10. What more energy in autumn really means
11. References

Why autumn can make you tired

As the days get shorter, one of the most important environmental cues for the human body changes: daylight.

Light is not only there to help us see. Specialised cells in the retina register the brightness of our surroundings and relay this information to structures in the brain that control our circadian clock. This body clock influences sleep, alertness, body temperature, hormone release and metabolism, among other things.

The most important cue is the alternation between light and dark. Morning light is particularly relevant. It helps the body recognise the start of the biological day and synchronise the body clock with the environment.

In autumn, less natural light is available in the morning. At the same time, many people spend a large part of the day indoors. As a result, the difference between light and dark perceived by our circadian system can be much smaller than in summer.

However, this does not mean that everyone inevitably becomes more tired in autumn. Studies of seasonal changes in sleep and activity show a nuanced picture. Seasonal effects exist, but are often relatively small and differ between people.

Temperature, weather, daily routines and personal habits also change with the seasons. People who spend less time outdoors in autumn, exercise less and spend longer in front of screens late in the evening may therefore feel more exhausted for several reasons.

Autumn tiredness is not the same as winter depression

Temporary tiredness is, in the first instance, different from seasonal depression. Seasonal affective disorder, often referred to as Seasonal Affective Disorder, is a form of depression in which depressive episodes repeatedly occur at a particular time of year.

Alongside low mood, typical symptoms may include lack of motivation, social withdrawal, increased sleep and changes in appetite. The condition is much more than a few tired autumn days and should receive appropriate medical treatment.

Light therapy is an established treatment for people with seasonal depression. However, this does not automatically imply that a bright lamp in the living room gives healthy people more energy.

The distinction matters: More daylight in everyday life is useful; light therapy is a medical treatment.

Light sets the pace for our body clock

The effect of light on the body begins in the retina. This contains so-called intrinsically photosensitive retinal ganglion cells. They contain the light-sensitive pigment melanopsin and respond particularly to short-wavelength components of light.

From there, the signal reaches the suprachiasmatic nucleus in the hypothalamus, among other areas. It is often described as the central human biological clock.

This clock coordinates numerous processes in the body. One is the regulation of melatonin. More of this hormone is released in darkness, signalling to the organism that the biological night has begun.

Morning light can influence this rhythm. Timing is crucial. Brightness at different times of day can shift the body clock in different directions.

This makes autumn interesting for the circadian rhythm. Not necessarily because the body suddenly needs more sleep, but because the morning light signal changes.

More daylight is simpler than a complicated morning routine

The practical consequence is surprisingly unremarkable: if possible, go outside in the morning.

A walk to work, a loop around the block or a short journey on foot can be more than exercise. It also brings daylight and physical activity into the morning.

This is particularly worthwhile in autumn, because even an overcast sky outdoors can be much brighter than typical indoor lighting. However, the actual amount of light depends strongly on the weather, time of day and surroundings.

A study of office workers showed that greater exposure to circadian-effective light in the morning was associated with better sleep quality and a shorter time to fall asleep, particularly in winter. Such observational data can show associations, but do not prove that more morning light alone causes better sleep.

Systematic reviews reach a similar but cautious conclusion: the timing and intensity of light exposure can influence the sleep–wake rhythm, but evidence from normal everyday life is not clear on every point.

What happens in the evening is also relevant

The circadian rhythm is not influenced only in the morning. Bright light in the evening can also shift the body clock and influence melatonin release.

This does not mean that every smartphone automatically ruins sleep in the evening. The actual effect depends on brightness, duration, the interval before bedtime and individual sensitivity, among other factors.

Nevertheless, a simple rule is plausible: As much natural light as possible in the morning, and progressively less bright light in the evening.

This fits human biology better than a constantly bright day followed by an abrupt switch to complete darkness.

Why sleep becomes particularly important in autumn

More energy does not begin with staying awake for as long as possible. Much of it develops during the time when the body does not have to perform.

Sleep influences attention, memory, emotional regulation and numerous metabolic processes. At the same time, individual sleep needs vary. The frequently cited recommendation of seven to eight hours describes a range associated with particularly favourable health parameters in large reviews of studies. However, this does not mean that everyone needs exactly this amount of sleep.

Personal sleep rhythms can change in autumn. Less daylight in the morning and more darkness in the evening can influence the timing of the body clock. At the same time, many people's daily routines change.

People who get up later in the morning because it is still dark outside and stay in artificial light longer in the evening can shift their rhythm further.

Regularity matters more than a perfect sleep plan

Duration is not the only thing that matters for sleep quality. A sleep–wake rhythm that is as regular as possible can also help.

This does not mean that every deviation at the weekend is problematic. Rather, the aim is to give the body reasonably reliable times for sleeping and getting up.

Simple habits can help:

• get up at roughly the same time in the morning
• get daylight as early in the day as possible
• choose gentler lighting in the evening
• avoid continuing intensive work or stimulating content right up until falling asleep
• keep the bedroom dark, quiet and at a comfortable temperature

Also, caffeine deserves attention. A systematic review and meta-analysis of 24 studies showed that caffeine consumption can impair subsequent sleep. What matters particularly is not only the amount, but also the timing.

A cup of coffee in the morning is therefore different from a large coffee in the late afternoon.

Exercise works differently from what you might first think

When it is cold, wet and dark outside, many people feel less motivated to exercise. That is understandable. Physiologically, however, being even less active when tired is not necessarily the best strategy.

A systematic review and meta-analysis of 81 randomised studies involving more than 7,000 participants examined how regular training affects subjective energy, tiredness and vitality. On average, the results showed less tiredness and greater perceived energy and vitality.

Exercise does not have to be particularly intensive. The training programmes studied varied, and the effects differed depending on intensity and type of training.

For everyday life, this means above all: Exercise can not only use energy, but also help you feel more energetic.

Why this might work

Physical activity influences numerous systems simultaneously. It challenges the cardiovascular system and muscles, changes metabolic processes and affects the nervous system.

Regular training can also increase physical performance. Activities that were previously strenuous then require relatively fewer physical resources.

The interaction with sleep is also interesting. Exercise and sleep influence one another, although the relationships are more complex than the simple idea that ‘more exercise equals better sleep’. Systematic investigations do show associations, but not always the same effects in all populations.

Exercise therefore does not have to be seen as another project in an already busy day. A daily walk, cycling, climbing stairs or a short training session can already be useful.

Outdoors is particularly practical

An autumn walk combines several factors that may be relevant to feeling energetic: exercise, daylight and a break from long periods of sitting.

This combination in particular makes walking a surprisingly efficient habit.

The aim does not have to be reaching a certain step count every day. It is much more important to build regular exercise into everyday life and interrupt long periods of complete inactivity.

Diet for stable energy in everyday life

Energy from food initially means something very concrete: the body needs energy to supply the brain, muscles, organs and metabolic processes.

Nevertheless, a person's sense of energy cannot simply be inferred from calorie intake. How regularly they eat, which nutrients meals provide and how their individual metabolism responds to the diet also matter.

A balanced diet with sufficient protein, fibre, complex carbohydrates, unsaturated fatty acids, vitamins and minerals offers a solid foundation.

Meals that combine several of these components are particularly practical. Examples include oats with yoghurt and nuts, wholegrain bread with egg and vegetables, or a hot meal made from pulses, vegetables and a source of protein.

Not every slump is a nutrient deficiency

Particularly in autumn, tiredness and exhaustion are quickly attributed to a supposed vitamin deficiency. Scientifically, this is too sweeping.

An actual nutrient deficiency can cause tiredness. This applies to iron deficiency, for example. A systematic review of randomised studies found a reduction in subjective tiredness with iron supplementation in adults with iron deficiency without anaemia, while objective improvements in physical performance could not be clearly demonstrated.

This is an important distinction. Supplements are not a general source of energy. They can be useful when inadequate intake or a deficiency actually exists.

It is therefore not a good idea to take high doses of iron or other micronutrients on suspicion alone. For persistent tiredness, medical assessment may be more useful than an indiscriminate choice of dietary supplements.

Fluids are also part of everyday life

We sweat less in autumn than in midsummer. This can make us feel less thirsty. Nevertheless, fluids remain important for normal bodily functions.

However, research into the relationship between hydration status and cognitive performance is less clear than some popular recommendations suggest. Systematic reviews reach differing conclusions.

Above all, this allows a simple conclusion: drink regularly, without turning it into a complicated optimisation project.

Putting vitamin D in autumn into perspective

Vitamin D has a particular place in the context of autumn and winter. The body can produce vitamin D in the skin under the influence of UV-B radiation. As UV-B exposure decreases, the body's own vitamin D synthesis therefore changes.

Vitamin D is involved, among other things, in maintaining normal bones and normal muscle function. The European Food Safety Authority has scientifically assessed corresponding reference values and authorised health claims for this.

However, this does not mean that all autumn tiredness is due to vitamin D deficiency.

A randomised, placebo-controlled study of 120 healthy adults with vitamin D deficiency and tiredness did show a greater improvement in subjective tiredness following a single high dose of vitamin D than with placebo. The results are interesting, but are not sufficient to regard vitamin D as a general remedy for seasonal tiredness.

The starting point is crucial: A deficiency is different from an adequate supply.

People who suspect vitamin D deficiency or belong to a risk group should have this medically assessed. Blanket high-dose supplementation without a reason is not the right approach.

Coffee, alcohol and other energy drains

The quick energy boost from coffee does indeed work. Caffeine blocks adenosine receptors in the brain. Adenosine is involved in the build-up of sleep pressure, among other things. When its effect is temporarily reduced, we feel more alert.

Problems arise particularly when caffeine is used to mask chronic sleep deprivation.

A coffee in the afternoon may seem helpful in the short term, while also impairing sleep the following night. This can create a cycle: poor sleep, more tiredness the next day, more caffeine and poorer sleep again.

Alcohol is also often underestimated. Although it can make falling asleep easier, it changes sleep architecture and can impair sleep quality. People who feel exhausted the next morning despite spending enough time in bed should therefore look beyond the number of hours slept.

The best energy source is often less spectacular

Many supposed energy boosters work through a short-term stimulus. Coffee, sugar or stimulating products can change the subjective sense of alertness.

Over the long term, however, the foundations matter more: sleep, light, exercise and a balanced diet.

This sounds less exciting, but that is precisely what makes it interesting. These factors influence several biological systems simultaneously and do not have to be optimised afresh every day.

Small habits with a big impact

More energy in autumn does not have to mean changing your entire daily routine. Small changes are often more realistic and sustainable.

A useful daily rhythm could look like this, for example:

The aim is not to implement every point perfectly every day. The body does not operate according to a checklist.

What is more interesting is the combination of small signals. Light gives the body clock a sense of timing. Exercise challenges the body. Regular sleep allows recovery. A balanced diet supplies energy and nutrients.

Together, these factors create an environment in which the organism can adapt better to the changed seasonal rhythm.

When tiredness is no longer just seasonal

Not all tiredness in autumn is a normal response to shorter days.

If exhaustion persists for a long time, becomes much worse or interferes with everyday life, it should not simply be attributed to the season. Tiredness can have many causes, including sleep disorders, psychological strain, infections, anaemia, thyroid disease or other physical conditions.

Also, medicines can play a role.

The German S3 guideline on tiredness and exhaustion therefore recommends a structured assessment that, alongside sleep, pre-existing conditions and psychosocial factors, includes a physical examination and, depending on the situation, laboratory investigations.

It is particularly important to ask whether other symptoms are also present. Unusual weight changes, persistent fever, shortness of breath, severe pain, pronounced depressive symptoms or a marked deterioration in physical performance should receive medical assessment.

A marked seasonal decline in mood is also different from an ordinary autumn slump. Recurring depressive symptoms may be due to seasonal depression, for which targeted treatments are available.

What more energy in autumn really means

Autumn cannot simply be optimised away. Less daylight is part of the season and influences the environment in which our body clock operates. At the same time, people respond to it very differently.

The good news is that some of the most important adjustments are surprisingly down to earth.

Morning daylight, regular exercise, sufficient sleep and a balanced diet provide a much better foundation for an energetic daily life than promises of a short-term energy boost. Caffeine can temporarily increase alertness, but should not become a substitute for sleep. Vitamin D and other micronutrients are important when an adequate supply is lacking, but are not a blanket remedy for autumn tiredness.

Science also points more towards an interplay of factors than a single decisive trick. Light influences the body clock, exercise affects energy and tiredness, sleep supports recovery and diet provides the necessary foundation for metabolism.

More energy in autumn therefore does not mean fighting against the season. Rather, it means giving your body the signals and conditions that support its natural rhythm.

References

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