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Nutrition6 min read

ANABOLIC RESISTANCE AFTER 40: A MASTERS CYCLIST’S PROTEIN GUIDE

By Anthony WalshUpdated

WHAT WE BELIEVE & WHY

  1. 01Masters-athlete evidence does not currently establish one population-specific protein recommendation.

    Strong
    Roadman Position
    The best 2025 synthesis found only 12 heterogeneous studies, so Roadman will not turn a general sports-nutrition range into a masters requirement.
    Evidence Source
    Franzke et al., Nutrients, PMID 39940356
    Practical Implication
  2. 02A pooled acute analysis estimated a higher relative protein dose for maximal muscle-protein-synthesis response in healthy older men than in younger men.

    Moderate
    Roadman Position
    This supports reviewing meal adequacy; it is not a daily masters-cyclist target or evidence about women, performance or long-term outcomes.
    Evidence Source
    Moore et al., Journals of Gerontology, PMID 25056502
    Practical Implication
  3. 03A small eight-week randomized trial found no measured advantage of even versus uneven protein distribution in older adults at the intake tested.

    Emerging
    Roadman Position
    Even distribution can be convenient, but four equal feedings are not an established universal rule.
    Evidence Source
    Kim et al., Clinical Nutrition, PMID 28318687
    Practical Implication
  4. 04In an acute randomized trial of 48 healthy older men, 40 g pre-sleep casein increased overnight myofibrillar protein synthesis versus placebo.

    Moderate
    Roadman Position
    That physiological result does not prove a compulsory bedtime dose or long-term cycling-performance benefit.
    Evidence Source
    Kouw et al., Journal of Nutrition, PMID 28855419
    Practical Implication
  5. 05Problematic low energy availability can affect health and performance in female and male athletes.

    Strong
    Roadman Position
    Take persistent under-fuelling and symptoms seriously, but do not diagnose REDs from one calorie or energy-availability calculation.
    Evidence Source
    2023 IOC consensus statement on Relative Energy Deficiency in Sport
    Practical Implication

WHO THIS IS FOR

IS THIS YOU?

  • Masters cyclists deciding whether age changes their protein needs
  • Riders considering a high-protein, evenly distributed or pre-sleep protocol
  • Cyclists trying to change body composition without compromising training
  • Coaches who need clear boundaries between acute physiology and individual nutrition advice

THE ROADMAN VIEW

The Roadman View

  • Protein matters, but a precise target without energy, carbohydrate, diet and health context is false precision.
  • An acute muscle-protein-synthesis result does not automatically become a long-term cycling-performance protocol.
  • The first job is to find the real gap; the second is to change one input and reassess.

Anabolic resistance is a real research concept. “Every masters cyclist needs 1.6–2.2 g/kg, four equal meals and casein before bed” is a much stronger claim—and the masters-specific evidence does not establish it.

The useful middle ground is to take muscle maintenance and protein adequacy seriously without pretending that age creates one diet. Total energy, carbohydrate, training, body size, dietary pattern, goals, appetite, gastrointestinal tolerance and health all change the decision.

This article explains the anabolic-resistance question. Use the masters nutrition hub for the full energy-carbohydrate-protein audit, the canonical protein guide for the general cyclist question and the bedtime protein review for pre-sleep evidence.

The direct answer

Anabolic resistance describes a lower muscle-protein-synthesis response to a given anabolic stimulus in some ageing research. A pooled analysis of acute feeding studies estimated that healthy older men reached a muscle-protein-synthesis plateau at a higher relative protein dose than younger men.

That result can support checking whether a low-protein meal is adequate. It does not determine a daily intake for a masters cyclist, establish a four-meal rule, represent women, or prove a long-term performance outcome.

The most direct masters-athlete synthesis is a 2025 scoping review. It found only 12 heterogeneous reports across endurance, multi-sport and strength-trained athletes. Reported average protein intakes ranged from 1.0 to 1.9 g/kg/day. The authors said population-specific recommendations were uncertain or speculative and called for better research.

That evidence gap matters. A range used in general sports nutrition may be a starting reference for a qualified practitioner; it is not automatically a requirement created by a fortieth birthday.

Start with total energy and carbohydrate

Protein cannot fix a diet that does not support the training load. Before changing grams per kilogram, ask:

  • Is body mass changing intentionally or unexpectedly?
  • Are long and demanding rides fuelled before and during the work?
  • Does the rider have access to a normal meal or snack after training?
  • Are training quality, recovery, sleep, mood or concentration deteriorating?
  • Are there recurrent injuries, illness or other symptoms?

The IOC REDs consensus describes how problematic low energy availability can affect health and performance in female and male athletes. It also makes clear that the syndrome is complex. One calorie estimate does not diagnose it.

An observational study of 108 competitively trained male endurance athletes classified many participants at risk using estimated energy availability and found lower values among cyclists than runners in that cohort. The authors warned that the cut-points were derived from female research and required validation for men. It is a reason to investigate chronic under-fuelling—not a diagnostic shortcut.

Use the fuelling self-assessment to find obvious gaps and the in-ride nutrition guide for the training-specific carbohydrate question.

What can a per-meal dose tell us?

Acute tracer studies measure a short-term physiological response under controlled conditions. They are valuable for mechanism, but they do not by themselves tell us which meal pattern produces the best performance, strength, body composition or health over months.

The Moore analysis estimated a larger relative meal dose for the older men in the pooled data. But a small eight-week randomized trial at about 1.1 g/kg/day found no difference between even and uneven protein distribution in measured lean mass, strength, function or protein kinetics among 14 older adults.

The studies answer different questions. Together, they support a practical review:

  1. Estimate current daily intake rather than assuming it is low.
  2. Find meals that contribute little protein.
  3. Decide whether changing one meal is useful and tolerable.
  4. Reassess the overall diet, training and outcome.

An even pattern can be convenient. It is not mandatory. A rider who prefers three meals, eats an adequate diet and performs well has not failed a proven four-feeding protocol.

Does protein before sleep matter more after 40?

In a randomized acute trial, 48 healthy older men received 40 g casein, 20 g casein, 20 g casein plus leucine or placebo before sleep. The 40 g condition increased overnight myofibrillar protein synthesis compared with placebo.

The correct inference is specific: pre-sleep casein was digested and affected overnight muscle-protein synthesis in that population and setting. The trial did not test masters cyclists, women, long-term recovery, sleep quality, race performance or whether bedtime protein outperforms fixing breakfast, total intake or post-training access to food.

Pre-sleep protein can be an optional way to distribute intake when the rest of the diet is adequate and the rider tolerates it. It is not one of the “must-do” rules of ageing.

Body composition is not an instruction to chase the lowest weight

Climbing performance can depend on both power and mass. That does not make every reduction in body mass beneficial. Restriction can reduce training quality and may compromise lean mass, recovery and health. The body-composition guide separates those outcomes; the lighter-is-faster review explains why scale weight alone is an incomplete target.

If weight change is appropriate, use a gradual, monitored process. Protect the sessions that matter, track performance and health as well as weight, and do not assume that a high protein intake neutralises an aggressive deficit.

A decision table for masters cyclists

SituationFirst actionWhat not to infer
Breakfast contains little proteinReview the whole day's intake and test a practical changeThat four equal meals are compulsory
Total intake appears low during a heavy blockCheck energy and carbohydrate alongside proteinThat protein alone will restore recovery
A rider wants a bedtime snackConsider preference, tolerance and total intakeThat 40 g casein guarantees better cycling performance
Weight is falling and performance is decliningStop treating it as a simple race-weight projectThat age or anabolic resistance is the diagnosis
Kidney disease, diabetes or another clinical condition is presentUse an appropriate clinician and sports dietitianThat a general athlete range is safe or suitable

When to seek individual help

A registered sports dietitian can assess dietary records, training demands, preferences and the goal together. Qualified clinical assessment matters for rapid or unexplained weight change, recurrent injury or illness, persistent fatigue, menstrual disturbance, disordered eating, suspected low energy availability or a condition such as kidney disease or diabetes.

Roadman provides education and coaching. It does not diagnose REDs or sarcopenia, prescribe a therapeutic diet, or set individual protein and energy targets for a clinical condition.

Primary sources and review boundary

These sources define what this guide can and cannot infer. They do not validate Roadman's decision table as a clinical tool or establish one masters-cyclist diet.

FAQ

FREQUENTLY ASKED QUESTIONS

What is anabolic resistance?
It describes a lower muscle-protein-synthesis response to a given protein or exercise stimulus in some ageing research. It makes protein adequacy worth reviewing, but it does not prove that every masters cyclist needs the same daily intake, meal size or supplement.
How much protein should a masters cyclist eat?
Masters-specific research does not establish one universal target. Assess current intake, total energy, carbohydrate, body size, dietary pattern, training, goals and health. A registered sports dietitian can turn that context into an individual recommendation.
Do masters cyclists need 30–40 g of protein four times a day?
No trial establishes that as a compulsory pattern. A larger meal dose may stimulate more acute muscle protein synthesis in older men, while a small eight-week trial found no outcome advantage for even versus uneven distribution at the intake tested.
Does casein before bed improve cycling recovery?
An acute trial in healthy older men found 40 g casein increased overnight muscle protein synthesis versus placebo. It did not test long-term cycling performance, women, sleep quality or whether bedtime protein is better than correcting low intake elsewhere in the day.
Should a masters cyclist cut calories to improve climbing?
Sometimes weight change may help, but age alone cannot decide it. Protect key training, use a gradual process, monitor health and performance as well as body composition, and seek help if restriction, symptoms or rapid weight change becomes concerning.
When should nutrition advice come from a clinician or sports dietitian?
Seek individual assessment for rapid or unexplained weight change, recurrent injury or illness, persistent fatigue, menstrual disturbance, disordered eating, suspected low energy availability, or conditions such as kidney disease or diabetes that change nutrition decisions.

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AW

ANTHONY WALSH

Host of the Roadman Cycling Podcast