猛暑・大暑の夏こそ手帳の出番|引き算の手帳術で夏バテを乗り切る4つの方法

Diaries and Planners for a Scorching Summer: 4 Ways to Beat Summer Fatigue with "Subtraction" Planning

☀️ 24 Solar Terms・Summer Diary Methods

Summer's intense heat is when your diary shines.
4 "Subtractive Diary Methods" learned from Taisho (Greater Heat)

Don't push yourself on hot days. Just deciding what not to do can change your summer. We introduce Forte Diary's unique subtractive diary methods.

📅 July 2026 ⏱ Approx. 4 min read ✍ Forte Diary
🌞

Are you overfilling your schedule on intensely hot days?
Summer's intense heat is the season to "subtract" with your diary.

The 24 Solar Terms "Taisho" teaches us how to wisely spend the summer.

Current
Taisho (Greater Heat)
July 23rd - August 6th

July 23rd marks "Taisho" (Greater Heat) in the 24 Solar Terms. During this period, said to be the hottest of the year, temperatures consistently exceed 35 degrees Celsius, gradually draining both body and mind.

What often happens during this intense summer heat is that we try to cram in tasks, thinking "I have to do it even if it's hot." However, heat affects not only physical strength but also concentration and judgment. The intense summer heat is the season to "subtract" with your diary.

✦ What is Taisho (Greater Heat)?

The 12th of the 24 Solar Terms. Meaning "the greatest heat," it is the period when the heat is most severe throughout the year. In 2026, it runs from July 23rd to August 6th. This period also overlaps with the summer Doyo (intercalary period), and the Day of the Ox during Doyo (July 26th in 2026) falls around this time. When the next solar term, Risshu (Beginning of Autumn) (August 7th), arrives, autumn officially begins on the calendar.

① Decide "what not to do" and do the rest in the morning

📋 Using a Weekly Planner

Write a "do not do list" the night before an intensely hot day

On hot days, it's said that physical strength and concentration are at 70-80% of normal levels. If you try to complete your usual tasks, you'll be exhausted both physically and mentally by evening.

In the memo section on the left side of your Weekly Planner, after listing your next day's schedule, first choose what you'll decide "not to do today." Only what remains is truly necessary for the day.

📋 Examples of "subtraction" entries for intensely hot days
Do not doReplies, document creation, research that can be postponed
Do not doGoing out in the scorching sun, daytime shopping
Do not doDecisions requiring mental effort, important meetings (if possible)
Do in the morningWork requiring concentration, important emails
Do in the morningGoing out, shopping, exercise
Do in the eveningLight tasks after the temperature drops

Focusing on the remaining tasks during the "cool morning hours" after subtracting others will surprisingly change your performance on intensely hot days.

✦ FORTE DIARY TIPS

Forte Diary's Weekly Planner is designed so you list "to-dos and not-to-dos" in the grid notebook on the left, then allocate them by time slot in the calendar on the right. This naturally creates a flow of "subtracting before arranging."

② Write summer fatigue prevention as a "plan" in your diary

📅 Using a Monthly Planner

Make health management a "plan" rather than a "to-do"

Preventing summer fatigue is much easier than dealing with it after it occurs. However, staying hydrated and ensuring enough sleep tend to be put off on busy days if you only "vaguely intend to do them."

📋 Examples of summer fatigue prevention entries in Monthly Planner
From 7/23Taisho starts: Drink a glass of water every morning upon waking
7/26Day of the Ox during Doyo: Eat eel or something nutritious
WeeklyGo to bed 30 minutes earlier (protect sleep quality)
From 8/7Risshu: Reflect on summer fatigue and prepare to resume pace for September

Just by having the mindset that "health management is part of the plan," your chances of staying well through the latter half of summer significantly increase. If it's written on the calendar, you'll see it even on busy days.

③ Journal your shifting emotions due to the intense heat

Heat also affects mental well-being. Increased irritability, lack of motivation, and feeling like doing nothing are partly due to autonomic nervous system imbalances caused by high temperatures. Many people blame themselves for "being unable to do anything because of the heat."

However, it's because of the heat. Try journaling these emotions as they are on Forte Diary's Journal pages.

✍ Journaling during intense heat - things to write about

① How does your body feel today?

Tired, heavy, headachey—write honestly. Just acknowledging "I'm in this state because of the heat today" reduces self-loathing.

② Write one thing you accomplished today.

No matter how small. "Drank water regularly" or "Rested in a cool room" are valid accomplishments.

③ A word for your future self tomorrow.

"Don't push yourself," "It's supposed to be a little cooler tomorrow"—small words for your future self can change your mood the next morning.

✦ Things to know

Irritability and low mood on intensely hot days are due to changes in atmospheric pressure, temperature, and humidity affecting the autonomic nervous system. This phenomenon is called "weather-related illness," and it's not just your imagination. Journaling your emotions helps you objectively perceive "this is due to the heat."

④ From Taisho to Risshu - design the latter half by being aware of "the end of summer"

The next solar term after Taisho is "Risshu" (Beginning of Autumn) (August 7th). On the calendar, it marks the start of autumn. While it's hard to feel when you're in the midst of intense heat, writing down "things you want to do before summer ends" in your Monthly Planner during Taisho will help you have a summer without regrets.

📋 Examples of "by the end of summer" entries
By AugustInclude one unique summer experience (fireworks, beach, BBQ)
By AugustCreate summer memories with children and family
8/7Risshu: Journal to reflect on summer fatigue
Towards SeptemberList goals and things you want to do for the latter half and start preparing for autumn

Because you know the "milestone" of Taisho, you can operate within a short span of "from here to Risshu." The reason Forte Diary's Monthly Planner includes Taisho is so you can naturally incorporate such conscious divisions into your daily life.

The intense summer heat is a season for not pushing yourself. But by organizing "what not to do" and "what's important" with your diary, you'll find your own time amidst the hot days.

✦ Forte Diary

A diary where the 24 Solar Terms mark the changing seasons.

The words of Taisho and Risshu noted in the Monthly Planner
naturally help you organize how you spend your summer.

Explore Forte Diary →

Just by turning the pages, you'll understand how to use it 📖

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