The 90-Day Reserve Plan
A planning workbook

Built for What Happens Next

The 90-Day Reserve Plan. Turn a broad health intention into one measurable project.

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What physical reserve means

Most days ask the body for an amount it can comfortably provide. A harder stretch may add illness, travel, physical work, caregiving, or disrupted sleep.

The room between those demands and your current capacity is what this workbook calls reserve.

Several measurable qualities contribute to it. Skeletal muscle helps produce force. Aerobic capacity supports sustained work. Bone provides structure. Resting energy expenditure adds context for the nutrition and recovery supporting the plan.

How to use this workbook

Physical reserve is a planning concept rather than a clinical score. This workbook helps you choose one demand you want to handle better, define how progress will be judged, and identify which parts of the plan are currently measured or estimated. It provides planning questions rather than an individual exercise prescription.

It takes about fifteen minutes. Your answers stay in this browser and print with the plan at the end.

Your turn

Choose the demand you want to handle better

Start with life rather than with a metric. Something specific you want your body to manage more easily ninety days from now.

People often name an upcoming hiking trip, a season of travel, keeping up with a five-year-old, a return to lifting after a long gap, or simply finishing a long workday with energy left for the evening.

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The four parts of reserve

Reserve does not reduce to one number, so the useful question is which part needs attention first. Each part can be examined using measurements, habits, and the appropriate health or performance context.

Muscle

Skeletal muscle produces force and helps your body manage physical work.

A DEXA scan estimates lean soft tissue, which includes more than skeletal muscle. It can track lean-soft-tissue changes when scans are completed under comparable conditions, and it does not isolate muscle or measure strength.

Bone

Bone carries the load and changes over years rather than weeks.

DEXA bone density adds context. A ninety-day block can establish the loading and nutrition you intend to follow, while a meaningful density change needs a longer horizon. Diagnostic bone questions belong with a qualified clinician.

Aerobic capacity

This is how much oxygen your body can use during hard work, and it sets the ceiling everything else runs under.

A metabolic test measures it directly by analyzing the gases you breathe. A wearable calculates an estimate without them.

Energy support

Adaptation depends partly on adequate energy and recovery.

An RMR test measures resting energy expenditure under controlled conditions. It does not measure what you eat or your total daily need.

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What a DEXA scan adds

DEXA stands for dual-energy X-ray absorptiometry. It separates your body weight into fat, lean soft tissue, and bone, and it reports where each sits rather than only how much there is.

That matters because the scale reports one number for four different things. Two people at the same weight can carry very different amounts of lean tissue, and the same person can lose fat and add lean tissue while the scale barely moves.

It also estimates visceral adipose tissue, the fat stored around your abdominal organs. Higher levels are associated with greater cardiometabolic risk, and the result belongs in the context of your full report and your broader health picture.

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What VO2 testing adds

VO2 max is the most oxygen your body can use during hard exercise, and it sets the ceiling that everything else operates under. Large research reviews consistently associate higher cardiorespiratory fitness with lower risk of mortality and several chronic conditions.

A lab-based metabolic test also finds your ventilatory thresholds, the two points where your breathing changes character as effort rises. Those thresholds are what turn a training zone from a guess into a real target.

Wearables can give you a useful trend, and their VO2 estimates are calculated without measuring the gases you breathe. Accuracy varies by device, by protocol, by fitness level, and from one person to the next. A metabolic test measures the gases directly and finds the thresholds a wearable estimate does not provide.

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What RMR testing adds

RMR stands for resting metabolic rate, the energy your body uses to support its basic functions while resting under controlled conditions. It accounts for the largest share of what you burn in a day, and it is measured by breathing into a device while you sit still.

Most calorie targets start from a population equation. The size and direction of the individual error remain unknown until resting energy expenditure is measured. A measured RMR replaces that first guess with a resting value collected from you under standard conditions, which gives nutrition planning a more personal starting point.

Your turn

Choose one 90-day outcome

Choose one primary outcome for the next 90 days. A focused goal makes the weekly plan easier to follow and the follow-up result easier to interpret.

Then choose a second result you want to protect. Someone reducing fat mass may want to protect lean soft tissue. Someone building aerobic capacity may want to maintain strength and recovery.

Your turn

Build the weekly plan

Build the plan around an ordinary week, including the interruptions you already expect. Choose an amount of training, nutrition support, and recovery that you can repeat consistently.

Your turn

Decide how progress will be judged

Set the decision rule before the follow-up. That makes it easier to compare the result with your original goal, the testing conditions, and normal measurement variation.

Two things make a change worth acting on. It has to be larger than the normal variation of whatever measured it, and it has to be taken under conditions close enough to the first reading to compare. Body weight moves day to day with hydration, glycogen, sodium, and food still in the digestive tract, so a consistent trend tells you more than one isolated reading.

What your plan currently rests on

Estimates still in the plan

Your 90-Day Reserve Plan

The demand I want to handle better
Not yet written
The part of reserve I am focused on
Not yet chosen
My primary outcome
Not yet chosen
The result I want to protect
Not yet chosen
My weekly plan
Not yet built
My decision rule
Not yet written
I will measure again
Not yet decided
Take this with you

Questions to bring to your appointment

Print the page above and bring it with you. These are the questions that turn a set of results into a decision.

  1. Which measurement is most relevant to the demand I wrote down?
  2. What amount of change would be meaningful for my primary outcome?
  3. Which testing conditions should be repeated at the follow-up?
  4. How should we monitor the result I want to protect?
  5. When would retesting provide enough information to guide the next decision?

Two more, for Seattle clients

Which constraint is capping my cardio capacity, and what does that change about how I train? And if I already have recent test results from another provider, can you review them to see whether they contain enough information to interpret?

Next step

Book comprehensive testing

A comprehensive testing bundle provides three different starting points. DEXA measures body composition and supplies available bone-density context. RMR measures resting energy expenditure. VO2 testing measures aerobic capacity and identifies individual training thresholds.

These results can replace several of the estimates you identified in the workbook. Bring your completed plan to the appointment so the measurements can be connected to your goal, your protection measure, and the decision you want to make after 90 days.

BodyScience interpretation

Testing gives you the numbers. Interpretation tells you which one deserves the next ninety days and what the program built around it looks like. If you already have recent results from another provider, send them over and we will review whether they carry enough detail to interpret without repeating the test.

This workbook is educational. It does not diagnose any condition, prescribe treatment, or replace care from your physician. Medication questions, including questions about GLP-1 medications, belong with your prescribing clinician.

"Physical reserve" is used here as a planning concept. It is not a validated clinical score.