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November 2, 2026

For people living with ME/CFS, and for those with Long COVID or other conditions who experience post-exertional malaise (PEM), a change in seasons may bring more than a change in the weather.

As the seasons shift, some people notice changes in their symptoms including increased fatigue, heaviness, pain, orthostatic symptoms, headaches, sensory sensitivity, sleep disruption, cognitive difficulty, or a decrease in their overall functional capacity.

The term “October Slide” is used by many people with chronic conditions to describe a worsening of symptoms during the autumn season.  But rather than focusing on one month, I find it helpful to consider the broader concept of seasonal transitions as potential exertional stressors.

Seasonal transitions happen throughout the year, and depending on where someone lives, each transition may bring a different combination of environmental and daily-life changes. 

Seasonal change is more than weather 

When we think about changing seasons, we often think about shifts in temperature, changes in clothing and foods, or the familiar traditions and decorations that accompany each season. But seasonal transitions often bring multiple environmental changes and daily-life demands at the same time.

Environmental changes may include: 

• Fluctuations in barometric pressure 
• Changes in temperature 
• Shifts in humidity 
• Wind and changing weather patterns
• Changes in daylight hours and light exposure 
• Seasonal allergens and other environmental exposures 

Daily-life changes may include: 

• Changes in sleep and circadian patterns 
• Shifts in school and work schedules 
• Medical appointments and healthcare demands
• Holidays, social activities, and family gatherings 
• Travel and transportation demands
• Household tasks and seasonal preparations 
• Changes in routines and caregiving responsibilities

Some seasonal changes may actually reduce certain stressors. Cooler temperatures, for example, may be easier to tolerate. But the transition itself may still require the body to adjust to multiple changing conditions.

For someone with limited functional capacity, those changing conditions can become another demand contributing to their total exertional load.

Considering the wider picture is particularly important when we think about PEM because exertion is not limited to physical activity. 

 

Cognitive, sensory, social and emotional, orthostatic, environmental, and other demands can all contribute to total exertional load.

 

Seasonal transition may be another layer to that cumulative load.

Think about capacity and total load

Imagine your functional capacity as the size of a bucket.

Every demand your body must manage can add water to that bucket. Physical activity, thinking, sensory input, being upright, social and emotional demands, poor sleep, pain, and other physiological stressors can all contribute to the total load. Environmental stressors can add to that same bucket.

The impact of an additional stressor often depends on how close you already are to your available capacity.

If you have some room in your bucket, an environmental change may be noticeable but manageable. If you are already functioning close to your capacity, that same environmental stressor may have a much greater impact.

For someone with moderate to severe ME/CFS, the activities already filling their bucket may be the most basic aspects of daily life: toileting, washing up, accessing food, sitting upright, having a conversation, or simply tolerating the sensory demands of light and sound.

Changes in barometric pressure, temperature, or sleep, for example, may be added to a bucket that is already quite full.

From a Pacing for PEM perspective, the question becomes less about: 

 

“Why can’t my body tolerate this weather?” 

 

and more about: 

 

“What is contributing to my total exertional load right now, and how can I adjust or support some of those demands to stay within my available capacity?” 

Recognize your own pattern 

We cannot control seasonal or environmental changes, but we can become better at recognizing how they affect our symptoms and functional capacity.

If certain seasons or weather patterns seem to affect you, begin by observing the patterns rather than assuming that weather is the cause of every symptom.

Consider:

• What changed in the environment? Was there a shift in temperature, barometric pressure, humidity, wind, allergens, daylight, or several things at once? 
• What has changed in my terms of symptoms or function? Did you notice more pain, head pressure or headache, orthostatic symptoms, brain fog, sensory sensitivity, poorer sleep, fatigue or heaviness? Did you have more difficulty sitting upright, getting to the bathroom, preparing food, tolerating conversation, or completing your usual self-care? 
• When did the response happen? Was it immediate? Later that evening? The following day? 
• What else was happening at the same time? Was there an appointment, a shower, a visitor, disrupted sleep, a longer period upright, or another activity that added to the overall load? 

Time is particularly important with PEM.

 

Changes in symptoms may not occur immediately. With PEM, symptom worsening can be delayed by hours or days, and the effects of multiple exertional demands may accumulate over time.

 

The goal is not to attribute a change in symptoms or function to one specific environmental stressor. It is to recognize patterns that can help guide decisions about activity, support, and rest.

Look ahead at cumulative load 

Looking at today’s weather can be helpful, but it is equally important to zoom out and consider the demands of the coming days.

A passing storm or rapid shift in temperature or barometric pressure may be associated with changes in symptoms or function. But seasonal transitions can also introduce multiple environmental and daily-life demands that overlap and accumulate across days or weeks.

Consider what your body is being asked to manage.

For example, Monday includes a shower or washing up. Tuesday brings a telehealth medical appointment. Wednesday brings a significant weather change, and Thursday includes a visit from a family member. By Friday, the cumulative impact of these demands may finally become apparent, with delayed PEM causing a significant increase in symptoms and a decline in functional capacity.

Each demand may appear manageable when viewed by itself, but together, they may exceed your current capacity.

For someone with significant functional limitations, even seemingly small changes can matter. Moving between rooms more often than usual, sitting upright for a telehealth appointment, having an extended conversation, changing clothing, or washing hair may represent significant exertional demands.

Rather than asking only:

 

“Can I do this activity?” 

 

Consider: 

 

“Can I do this activity within everything else my body is being asked to manage this week?” 

Also watch for changes in your baseline. Are symptoms becoming easier to trigger? Are activities that were previously manageable requiring more rest? Do you need more assistance with the activity? Are you starting the next day with symptoms or limitations that have carried over from the day before?

These may be signs that your available capacity has decreased or that your cumulative exertional load is exceeding what you can currently manage.

When capacity changes, pacing needs to change with it.

Adapting activities to changes in available capacity

As seasonal demands change, we can look for ways to reduce the exertional load of everyday activities. Sometimes this means modifying the activity itself by adjusting what we are trying to accomplish. Other times, it means adding accommodations that reduce the physical, cognitive, sensory, or orthostatic demands of participation.

The goal is not necessarily to eliminate meaningful activities, but to find ways to protect available capacity while preserving what matters most.

Adjusting the Activity: Modifications

What is the smallest version of this activity that still meets my needs?

Modifications involve adjusting the goal, amount, duration, or expectations of an activity to make it more manageable within available capacity.

• Could an activity be shortened or broken into smaller segments? 
• Could you reduce the number of tasks or steps involved?
• Could self-care and household tasks, such as changing clothes, doing laundry, restocking groceries, or preparing meals, be spread over several days rather than completed all at once?
• Could holiday plans or traditions be simplified? For example, could you attend a short portion of a gathering rather than the entire event, or choose one meaningful activity instead of several?
• Could you adjust expectations for social participation? For someone with more severe limitations, this might mean exchanging a short message rather than having a conversation or visit.
• Could some activities be postponed, eliminated, or delegated to others?

Reducing Exertional Load: Accommodations

How can I reduce the demands of an activity while preserving what matters to me?

Accommodations involve changing the environment, positioning, or supports used during an activity to reduce exertional load without necessarily changing the goal itself.

• Could you reduce light, noise, fragrances, or other environmental and sensory demands?
• Could you sit, recline, or elevate your legs rather than remain standing or upright?
• Could mobility aids, adaptive equipment, or other tools reduce physical or orthostatic demands?
• Could you use reminders, written instructions, or other cognitive supports to reduce cognitive effort?
• Could someone assist with the more demanding parts of an activity, such as seasonal household preparations, shopping, or meal preparation?
• Could you participate in a family gathering from a reclined position, a quieter room, or remotely rather than in a busy environment?
• For someone with severe functional limitations, could a meaningful seasonal tradition be brought to their bedside, with sensory input and interaction adjusted to their tolerance?
• Could frequently used supplies, seasonal clothing, or comfort items be kept within reach to reduce unnecessary movement?

Match the support to the demand 

Pacing for PEM involves recognizing which types of exertional demands are increasing and identifying accommodations that reduce those specific demands.

• If orthostatic symptoms are increasing, reduce upright demands where possible. Sitting, reclining, mobility supports, bedside supplies, or reducing unnecessary trips between rooms may help.

• If sensory symptoms are increasing, consider reducing light, sound, temperature, smells, screen time, and conversations. A quieter, darker, lower-stimulation environment may reduce that load.

• If cognitive symptoms are increasing, simplify information and decision-making. Reduce multitasking, shorten conversations, use written information or reminders, and allow another person to take over planning or communication when possible.

• If physical demands are increasing, look for ways to reduce walking, reaching, standing, transfers, or repeated movement and divide necessary activities into smaller parts.

Accommodations and support tools do not increase the size of the bucket itself, but they can reduce how much of your available capacity an activity uses.

Use preemptive and recuperative rest 

Rest does not have to happen only after symptoms intensify.

If you recognize that certain environmental changes, weather patterns, or seasonal activities tend to increase your exertional load, consider planning preemptive rest before the anticipated stressor.

Allow for recuperative rest afterward, even if symptoms have not yet intensified, particularly if you tend to experience delayed PEM.

Rest should also match what your body is experiencing.

• Orthostatic rest may mean reducing upright time and positioning your body with more support. 
• Cognitive rest may mean reducing conversation, screens, reading, decision-making, or other thinking demands.
• Sensory rest may mean a quieter, darker, lower-stimulation environment. 

The purpose of rest is not simply to stop activity, but to reduce the demands your body is struggling to manage.

The goal is to protect function. 

We cannot control the weather or stop the seasons from changing. But we can become better at recognizing how environmental changes interact with everything else the body is being asked to manage.

By observing immediate and delayed symptom responses, looking ahead at cumulative demands, and adapting activities and rest to changes in available capacity, we can better anticipate periods of increased exertional load.

For someone who experiences PEM, a seasonal increase in symptoms may not be the result of one isolated stressor. Seasonal transition may be one part of a much larger cumulative exertional load.

Recognizing these patterns gives us an opportunity to respond. This may mean temporarily reducing activities, adjusting routines, increasing rest, or reconsidering priorities when the body’s available capacity is more limited.

The goal is not to avoid seasonal change, but to recognize its potential impact, adjust demands we can control, and protect available capacity for the activities that matter most.

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Additional Resources

Lived Experience Resources:

Amy was interviewed for an October 20 piece in The Sick Times: The real story behind the “October slide”

Staying Within Your Energy Envelope by Modifying Tasks
Bateman Horne Center, Lunch & Learn: Pacing for PEM

Improving Quality of Life- Managing PEM and Chronic Illness
Make Visible Podcast – Episode 23

Provider Resources:

Pacing for PEM: Strategies to Protect Function & Improve Quality of Life
SILC Global Long Covid Project ECHO Webinar

Post-Exertional Malaise: Recognizing the Crash After Activity
Long COVID and Fatiguing Illness Recovery Program Project ECHO Webinar

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