Athlete Nutrition Periodization: Aligning with Training Phases for a Win-Win in Performance, Body Weight, and Recovery

Starting with an Athlete’s “Season Stall”

Over a decade ago, I coached a mountain biker—let’s call him A-Kai. That winter, he trained hard, and his power progressed rapidly. His 5-minute max power was so impressive that I’d smile looking at the data at midnight. But once the April race season hit, he deflated like a punctured tire. He’d dropped nearly three kilograms, looking lean, but in the latter part of races, he’d “hit a wall” on climbs—heart rate spiking to 180 bpm with no watts to show for it. When he came to me, his first words were: “Coach, I train harder than anyone. Why am I getting weaker the more I train?”

I asked him to pull out three months of food logs—the problem wasn’t training; it was eating. He had carried his “winter base phase” low-carb, fat-loss diet straight into the “in-season high-intensity phase”—like running a high-speed race on a car with only half a tank of fuel. His training was “periodized,” but his diet wasn’t.

This article is about the concept I’ve hammered home to athletes for years: athletes’ nutrition also needs periodization (nutrition periodization). Your carbohydrates, protein, total calories, and even body-weight goals should shift with the different phases of your season. This isn’t mystical—it has a physiological basis and practical methods. I’ll explain the concepts, tables, common mistakes, and actionable advice for readers at different levels, all from the perspective of actually coaching athletes.

Let me say one blunt thing upfront: this article is educational content. All numbers are ranges to point you in the right direction; for actual implementation, you must individualize.

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What Is “Nutrition Periodization”? Nailing Down the Concept

Everyone is familiar with “training periodization”—splitting a season into preparation (base) phase, progression (intensity) phase, competition (season/peak) phase, and transition (off-season/recovery) phase, each with different training volume and intensity. The core idea of nutrition periodization is simple:

Since each phase has different training demands, the fuel and repair materials supplied to support that training should change accordingly.

As I often tell athletes: “You don’t need to eat the same thing every day, and your body’s needs differ daily.” On low-training days, cramming in carbs just turns them into fat; on high-intensity days, under-fueling carbs means you can’t train, won’t adapt, and may push yourself toward the pit of “Relative Energy Deficiency in Sport (RED-S).”

I’ve met too many athletes who craft their “training plan” with great precision—power zones, interval sets, recovery weeks all dialed in—but when asked about eating, the answer is always, “I just eat normally.” The problem is, what does “normal” even mean? Normal in the base phase and normal in the race season are two completely different things. You’re willing to plan your training in phases, but you let your diet run on “one-size-fits-all”—that’s leaving half your effort at the door.

Nutrition periodization typically operates on three levels:

1. Season level (macro): Base vs. intensity vs. race season vs. off-season—the big-picture direction for total calories and body-weight goals.
2. Week level (meso): Within a week, the carbohydrate differences between heavy training days, recovery days, and complete rest days.
3. Individual session level (micro): Whether a specific workout is done “fully fueled” or “train low,” and how to refuel afterward.

This article focuses on the first two levels, because those are where most Taiwanese amateur and advanced athletes get things right—and wrong—most easily.

What Role Does Each Macronutrient Play in Periodization?

• Carbohydrates: This is the nutrient that needs periodization the most. It’s the primary fuel for high-intensity exercise, and muscle glycogen stores directly determine whether you can finish a hard session or race. Carbohydrate intake should fluctuate the most with training load.
• Protein: Relatively stable, but not completely static. It handles repair and adaptation, and demand rises during high-load blocks and post-race recovery.
• Fat: Usually plays the “filler role”—once carbs and protein are set, the remaining calories come from fat. In the base phase, fat can take up a higher percentage; in the race season, you can trim it to make room for carbs.

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The Science: Why Should Carbs Follow Your Training?

I’m not going to bury you in jargon, but if you grasp a few physiological facts, every table later will make sense—you’ll understand the “why” instead of memorizing.

First, glycogen is finite. The human body stores roughly enough glycogen to support 60 to 90 minutes of moderate-to-high-intensity exercise (actual figures vary by person and intensity). Once it’s depleted, your pace drops, heart rate runs artificially high, and focus starts to fade—that’s the physiological reason A-Kai “hit the wall” in the latter stages. The higher your training volume and intensity, the more glycogen you burn, and the more carbs you need to replenish it.

Second, there’s a widely cited range for carbohydrate intake. Based on current sports-nutrition guidelines, daily carbohydrate recommendations for athletes generally fall in the broad range of 3 to 12 grams per kilogram of body weight, adjusted by training intensity and volume: low-volume recovery periods lean toward 3 to 5 g/kg, moderate-to-high training volume around 6 to 10 g/kg, and extremely high loads (e.g., peak weeks for ultramarathons or multi-day races) approach 10 to 12 g/kg (see references at the end). This is why I keep stressing that “the amount must fluctuate”—no single number fits your entire season.

Third, the protein range is relatively clear. The International Society of Sports Nutrition (ISSN) position stand recommends athletes (including endurance athletes) consume roughly 1.4 to 2.0 grams of protein per kilogram of body weight per day; the harder, longer, or more demanding the training block—or the bigger the race aftermath—the closer you go to the upper end. Some research even suggests that around 1.8 g/kg or more may aid recovery during hard training blocks (see references at the end).

Here, I want to say a fair word for protein. Many endurance athletes think, “Protein is for people who lift weights,” and focus only on piling up carbs. Wrong. Endurance training also causes micro-damage and turnover in muscle tissue. With chronic protein deficiency, you’ll find yourself recovering slower, looking “flatter,” and getting sick more often. Protein doesn’t need to swing as wildly as carbs, but it’s a baseline you must hold all season—1.6 g/kg is my minimum requirement for serious athletes, and I push it toward 2.0 g/kg during hard blocks.

Fourth, “train low” doesn’t mean training hungry. The popular “train low, compete high” strategy deliberately keeps glycogen low during some low-intensity sessions to amplify mitochondrial adaptations. But it’s an advanced tool—used incorrectly, it can hurt you and tank performance. For most amateurs, my stance is conservative: get the basics of periodization right first, then talk about tricks.

Let me condense the four points above into a “quick-reference concept table”:

Physiological Fact	Meaning for Training	Meaning for Nutrition
Glycogen only lasts 60–90 min of moderate-high intensity	Long sessions/races will hit a wall late	Fuel up with carbs before and after high-intensity days and long rides
Daily carbs ~3–12 g/kg (by load)	Training volume determines fuel needs	Amount must fluctuate by season phase, not a fixed number
Protein ~1.4–2.0 g/kg	Material for repair and adaptation	Lean toward the upper end in high-load periods and post-race
Fat is the foundation for energy and hormones	Over-restricting fat harms recovery and endocrine function	Don’t chronically push fat extremely low

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Practical Approach: A Nutrition Blueprint for the Four Season Phases

Okay, concepts are done—now for what you really want: how to actually eat. I’ll use a hypothetical intermediate road cyclist, “Xiao-Min,” as the example: female, 55 kg, training about 8 to 12 hours per week, targeting a 100 km hilly race in the fall. All numbers below are “ranges and directions”—please scale them to your own situation.

Phase 1: Preparation / Base Phase (Winter, far from race season)

This phase focuses on high-volume, low-intensity aerobic work—large volume but low intensity. The goal is to build a foundation, manage body composition, and develop the body’s “efficiency.”

• Carbohydrates: Low-to-moderate, around 4 to 6 g/kg. On low-intensity days, this can drop to 3 to 4 g/kg.
• Protein: Maintain 1.6 to 1.8 g/kg to protect muscle and prevent muscle loss during any fat-loss period.
• Total calories: A mild deficit is acceptable (if weight loss is needed), but don’t cut too aggressively—aim for a weekly weight loss of 0.3 to 0.5 kg.
• Weight goals: This is the only period of the entire season suited for actively adjusting body weight. If you want to lose weight, do it here—don’t carry it into the race season.

My prescription for Xiao-Min: The base phase is her time to “lay the foundation and fine-tune body weight.” Carbohydrates stay low-to-moderate, protein is held at the upper end, and the fat percentage can be a bit higher (to support hormones and satiety).

Phase 2: Progression / Intensity Phase (Spring, race season approaching)

This is when you start adding high-intensity sessions like intervals, threshold work, and repeated climbs. Training volume may drop slightly, but intensity jumps significantly, and glycogen depletion becomes more aggressive.

• Carbohydrates: Clearly ramped up, around 6 to 8 g/kg, and higher on hard workout days.
• Protein: 1.7 to 2.0 g/kg, because the micro-damage from high-intensity work requires more repair material.
• Total calories: Shift to energy balance or a slight surplus. If you’re still aggressively cutting fat at this point, you’ll only find yourself unable to train and with a weakened immune system.
• Weight goals: Stop active weight loss. Focus on maintenance.

This is exactly the mistake A-Kai made back then—he carried his base-phase fat-loss diet into the intensity phase. The intensity went up, but the fuel didn’t follow, so the harder he trained, the weaker he got.

Phase 3: Race Phase / Season Peak (Race week and race day)

Training tapers, but intensity is maintained. The dietary focus shifts from “supporting training” to “filling the tank and maximizing race-day performance.”

• Pre-race carbohydrate loading: 1 to 2 days before the race, push carbohydrates up to about 8 to 10 g/kg, choosing easily digestible, high-glycemic sources. Research summaries indicate that a single day of high-carbohydrate loading before the race is nearly as effective as the traditional three-day approach (see references at the end).
• Pre-race meal: 3 to 4 hours before the start, eat a carbohydrate-focused meal that’s low in fat and fiber; 1 hour before, you can top up with a small amount of easily digestible carbs.
• In-race fueling: For events longer than 90 minutes, aim for about 30 to 60 grams of carbohydrate per hour (athletes with well-adapted guts can go higher), and pay attention to fluids and electrolytes.
• Protein: Just maintain it—don’t cut protein too low in the day or two before the race just to cram in carbohydrates.

Phase 4: Transition / Off-Season (After the race season ends)

Both mind and body need a breather. Training volume drops significantly, and the dietary focus is on repair, replenishment, and rebuilding—not immediately jumping into another fat-loss cycle.

• Carbohydrates: Back down to a low 3 to 5 g/kg.
• Protein: Maintain around 1.6 g/kg to support tissue repair.
• Total calories: Return to balance. Allow yourself some relaxation, but don’t let it spiral into a major weight spike, or you’ll have to chase it back from a long way off in the next base phase.

A Quick Overview of the Four Phases

Season Phase	Training Characteristics	Carbohydrates (g/kg)	Protein (g/kg)	Caloric Direction	Weight Strategy
Base Phase	High volume, low intensity	4–6 (3–4 on easy days)	1.6–1.8	Mild deficit	Actively adjust (weight loss OK)
Intensity Phase	High-intensity intervals	6–8 (higher on hard days)	1.7–2.0	Balance to slight surplus	Maintain, stop losing weight
Race/Peak	Taper, race	8–10 pre-race loading	Maintain	Sufficient	Maintain, no changes
Transition/Off-Season	Significant reduction	3–5	~1.6	Balance	Avoid major spikes

Using Xiao-Min’s 55 kg as a reference: base-phase carbohydrates are about 220 to 330 g/day, intensity phase about 330 to 440 g/day, and pre-race loading days can reach 440 to 550 g/day. You’ll notice that carbohydrates alone can differ by more than 200 g per day—this is exactly where people who don’t periodize their nutrition fall flat.

Converting g/kg into “Understandable Food Quantities”

Many athletes get overwhelmed when they see g/kg, but it becomes much friendlier once you translate it into everyday foods. I made a reference table of common carbohydrate foods for Xiao-Min (55 kg) so she could “count meals” instead of “weighing grams”:

Food	Portion	Approx. Carbohydrates	Practical Meaning
White rice	1 bowl (about 150 g)	About 55–60 g	Common base for a meal in the intensity phase
Sweet potato	1 medium	About 25–30 g	Easy to digest, race-friendly
Toast	1 slice	About 15 g	Option for the pre-race 1-hour top-up
Banana	1 piece	About 25 g	Easy to carry and eat during a ride
Energy gel	1 packet	About 20–25 g	Quick in-race fuel
Unsweetened soy milk + oats	1 serving	About 30–35 g	Breakfast covering both carbs and protein

For Xiao-Min’s intensity phase, she needs about 330 to 440 g of carbohydrates per day, which translates to roughly “three bowls of rice + two bananas + one sweet potato + one to two energy gels during training.” Once broken down like this, she immediately understood: “No wonder my base-phase diet was never enough to handle the intensity phase.” Translating abstract numbers into portions on a plate is, in my opinion, the single most important teaching step in nutrition periodization.

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Weekly-Level Application: Fluctuate Within the Week Too

Many people think periodization just means “eat this way for three months, then that way for the next three,” but fluctuation within a single week is just as critical. I teach athletes a simple principle:

Carbohydrates follow the training plan—high-carb on big training days, moderate-carb on recovery days, low-carb on complete rest days.

Using a typical week in Xiao-Min’s intensity phase as an example:

Day	Training Plan	Carbohydrate Strategy	Notes
Monday	Complete rest	Low (4–5 g/kg)	Keep protein up
Tuesday	Threshold intervals, 90 min	High (7–8 g/kg)	Fuel up before and after
Wednesday	Easy aerobic, 60 min	Moderate (5–6 g/kg)
Thursday	Repeated climbs (hard session)	High (7–8 g/kg)	Replenish carbs + protein within 30–60 min after
Friday	Recovery ride, 45 min	Low-to-moderate (4–5 g/kg)
Saturday	Long endurance, 3–4 hours	High (8+ g/kg)	Fuel continuously during the ride
Sunday	Rest or easy spin	Low (4 g/kg)

The benefit of this approach: you fill the tank on days when fuel is needed, and on days when it isn’t, you let the body rest while naturally controlling total calorie intake. Over the course of a week, you won’t underperform on hard sessions, and you won’t store excess calories on rest days.

Hydration and Electrolytes in Hot, Humid Conditions Also Need to “Follow the Training Plan”

In Taiwan’s summer, the focus of fueling isn’t just carbohydrates, but also fluids and sodium. Long rides produce a lot of sweat; if you only replace fluids without sodium, you risk diluting blood sodium levels. Here’s a rough but practical reference I give my athletes for long-ride fueling (actual sweat rates vary greatly, so please calibrate based on your own experience):

Training Scenario	Fluid per Hour	Sodium per Hour	Carbohydrates per Hour
Cool, under 90 min	Drink as thirst dictates	Usually no extra needed	Usually not necessary under 90 min
Hot & humid, 2–3 hours	Approx. 500–800 ml	Approx. 300–800 mg	Approx. 30–60 g
Hot & humid, long ride/race	Approx. 500–1000 ml	Approx. 500 mg–1 g or more	Approx. 60 g (higher if adapted)

I often remind my athletes: These numbers are a starting point, not a bible. Some people sweat over a liter per hour and lose a lot of sodium (the kind who get white salt crystals on their clothes); their needs will be significantly higher. The best approach is to experiment during training, record how you feel and your pre/post body weight, and gradually figure out your fueling rhythm before bringing it into races. Choosing early morning or evening training sessions in Taiwan’s summer is also part of incorporating environmental variables into your periodization.

Don’t Stress Too Much About the “Golden Window” for Post-Workout Fueling

Online forums often make the “30-minute golden window” after training sound like you’ve wasted all your effort if you don’t eat immediately. My practical attitude is much more relaxed: If you have a second session that day, or the session was particularly hard, then getting carbs + protein in soon after (about 1 g/kg of carbs, 20 to 30 g of protein) is indeed important; but if you only have one session a day and will eat regular meals afterward, relax—your next meals will naturally take care of it. Don’t be held hostage by marketing hype.

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Taiwan-Specific Context: Eating Out, Heat & Humidity, and Medical Care

Theory is theory, but Taiwanese athletes face several very practical variables in their daily lives that I always address with my athletes:

First, how to manage carbs and protein when eating out is the norm. A high percentage of Taiwanese people eat out. The upside is that carb sources are super convenient—a bowl of white rice has about 55 to 60 g of carbs, and sweet potatoes, noodles, and toast are all easy to estimate. Protein is the real pain point for those who eat out: bento boxes often have lots of vegetables but little meat. My advice is to make your protein intake per meal “visual”: a palm-sized portion of meat/fish/soy product is about 20 to 30 g of protein. Aim for 4 to 5 palms a day, and a 55 kg person will roughly hit their target. When you need more during high-intensity phases, adding a tea egg, a carton of unsweetened soy milk, or a chicken breast is a cheap and easy way to top up.

Second, the hot, humid climate makes fueling more critical. Taiwan’s summers are muggy, and long rides produce heavy sweat, amplifying the importance of electrolytes (especially sodium) and fluids. For training in hot, humid conditions lasting over 90 minutes, in addition to carb fueling, sodium intake is recommended at roughly several hundred milligrams to 1 gram per hour (needs vary greatly by individual and sweat rate; sodium loss can range from about 300 mg to over 1000 mg per liter of sweat). Training in the early morning or evening during summer, and choosing relatively cooler races in the season, are practical realities Taiwanese athletes must factor into their periodization.

Third, the healthcare system and access to medical care. Seeing a doctor in Taiwan is convenient—this is an advantage, so use it. If you experience persistent fatigue, menstrual irregularities (for women), recurrent colds, a noticeably elevated resting heart rate, or unexplained bone aches during tapering or high-intensity phases, don’t tough it out on your own or search randomly online—these could be signs of Relative Energy Deficiency in Sport (RED-S) or overtraining. Go see a sports medicine specialist or a sports dietitian. For those with chronic conditions (such as diabetes, hypertension, or heart disease), any major changes to dietary periodization must first be discussed with your primary care physician and dietitian, because large fluctuations in carbs directly affect blood sugar and medication. This is absolutely not something to do on your own.

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Common Mistakes and Fixes: The Six Pitfalls I See Most Often in My Athletes

After years of coaching, the mistakes in dietary periodization are highly repetitive. I’ve listed the six most common ones in a table, along with corrective directions:

Common Mistake	Why It’s Harmful	Corrective Direction
Eating the same all season (no fluctuation)	Under-fueled during intensity phases, excess calories during recovery	Fluctuate carbs according to season phase and training load
Still aggressively cutting fat during race season	Can’t train hard, immunity drops, muscle loss	Focus weight loss in the base phase, stop after intensity begins
Carbs too low during high-intensity phases	Glycogen depletion, bonking in the later stages	Increase carbs to 6–8 g/kg during intensity phases
Chronically insufficient protein	Slow recovery, getting weaker despite training	Maintain at least 1.6 g/kg all season
Chronically very low fat	Affects hormones and recovery	Don’t cut fat extremely low; keep a reasonable proportion
Blindly doing “low-carb training”	Using advanced methods without a foundation, performance drops	Master basic periodization first before considering it

I especially want to elaborate on the second pitfall: still cutting fat during race season, because this is the most common mistake among Taiwanese amateur athletes (especially cyclists who want to “lighten up” for climbing). Being lighter does help on climbs, but if the cost of being light is glycogen depletion and poor recovery, your power drops too, and being light is useless—climbing performance is about “power-to-weight ratio (W/kg),” not just body weight. If A-Kai loses three kilograms but his power also collapses, his W/kg is actually going down. Weight loss should happen at the right time, and you need to watch your power numbers alongside the scale, not just the scale.

Another point I want to highlight is energy availability for female athletes. Chronically low calorie and carb intake can lead to menstrual dysfunction and decreased bone density—this is a serious issue in sports medicine. I am especially conservative with female athletes when it comes to dietary periodization; any calorie reduction must have “no impact on menstruation and recovery” as a hard line. If anything seems off, seek medical advice first.

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Actionable Advice for Readers at Different Levels

Not everyone needs to calculate every gram. Based on your level, here are three approaches with different depths.

If You’re a Beginner (exercising 3–5 hours per week, not yet racing)

• Don’t rush into calculating g/kg. First, just follow the simple principle of “eat a bit more carbs on big training days, eat a bit less on rest days”—that alone puts you ahead of 80% of people.
• Aim for one palm of protein per meal, three to four portions a day. Don’t chronically undereat.
• Don’t chronically diet and exercise just to get skinny; you’ll get injured and fail to make progress.
• If you want to go further, start by logging what you eat for a week and comparing it to your training load—you’ll spot the gaps yourself.

If You’re an Intermediate Athlete (training 6–12 hours per week, with target races)

• Seriously divide your season into four phases, apply the g/kg ranges from the earlier table, and get the big picture right first.
• Within a week, fluctuate using “high-carb on big training days, low-carb on recovery days.”
• Do a carb load 1–2 days before a race, and rehearse your race fueling strategy during training (don’t try anything new for the first time on race day—your gut will protest).
• Weigh yourself regularly and monitor fatigue, resting heart rate, and sleep. Treat body signals as feedback.

If You’re an Advanced/Competitive Athlete

• You can consider more precise single-session manipulations (some low-carb training + high-carb key sessions), but it’s recommended to do this under the guidance of a sports dietitian.
• Closely track energy availability to avoid RED-S; female athletes especially should monitor their menstrual status.
• Build a team with your coach, dietitian, and (if necessary) a sports medicine physician, and plan dietary periodization as an integral part of your training program.

How Do You Know If Periodization Is “Working”? Monitoring Metrics

Dietary periodization isn’t something you set and forget—it requires feedback and fine-tuning. I have my athletes consistently track a few simple, free, at-home metrics and use their body’s signals as the basis for adjustments:

• Morning resting heart rate: If it’s noticeably elevated for several consecutive days (5 to 10 bpm higher than usual), it could indicate inadequate recovery or insufficient energy—time to review carbohydrate intake and sleep.
• Body weight trends: Look at the “weekly trend,” not the single-day number. If weight drops too fast during the base phase (more than 0.5 to 0.7 kg per week), the deficit is too aggressive—bring carbohydrates back up.
• Training performance: If the same workout shows a drop in power/pace, or an unusually high rating of perceived exertion (RPE), it’s often a sign of depleted glycogen.
• Sleep and mood: Chronic poor sleep, irritability, and lack of motivation are common precursors to overtraining and under-fueling.
• Menstrual status for women: Whether the cycle is regular is one of the most important indicators of energy availability. Any abnormality should be taken seriously and discussed with a physician.

I teach my athletes one key principle: when performance, heart rate, weight, sleep, and mood all trend in the wrong direction simultaneously, the first thing to suspect is usually not undertraining, but under-eating or insufficient recovery. In that case, the right move is usually “add carbohydrates, cut volume, sleep more”—not to push harder in training. Jot these metrics down in your phone’s notes app or training app, and you’ll have your own early warning system.

Frequently Asked Questions (FAQ)

Q: Is a low-carb (ketogenic) diet suitable for endurance athletes?
A: Some people may adapt well to it for “easy aerobic” work, but for races requiring high-intensity output, long-term very-low-carb intake may limit your peak performance. My stance is: if you want to try it, do so cautiously during the base phase and outside of race season—don’t risk your performance during the season, and consult a professional first.

Q: Does being lighter necessarily mean climbing faster?
A: No. Climbing depends on your power-to-weight ratio. If you lose weight but also lose power, or your recovery deteriorates, that’s a losing deal. If you want to lose weight, do it during the base phase while keeping an eye on your power numbers.

Q: I only do one session a day—do I need to worry much about post-workout nutrition?
A: No need to stress too much. Your normal meals afterward will naturally replenish glycogen. Post-workout fueling really matters for double sessions per day or particularly hard sessions.

Q: Will carbohydrate loading make me heavier and affect my race?
A: Storing glycogen does come with water retention, so a temporary weight increase is normal—and that water is actually a resource for you during the race. Don’t panic when you see the number on the scale.

Q: Can people with diabetes do carbohydrate periodization?
A: Large fluctuations in carbohydrate intake directly affect blood sugar and medication. This absolutely must be planned together with your primary care physician and dietitian—do not self-administer based on this article.

Q: I just exercise for general health and don’t race—do I need periodization too?
A: You don’t need to make it that complicated. Just follow the basic principle: “more carbohydrates on big training days, fewer on rest days, and a palm-sized portion of protein at every meal.” The finer details of periodization are for those with specific race goals who want to squeeze out peak performance.

Q: Will eating a lot of carbohydrates make me store fat?
A: The key is “total calories” and “timing.” On high-training-volume days, the extra carbohydrates mostly go toward replenishing glycogen. The problem arises when you “eat like a high-volume day on a low-volume day”—which is exactly why you should fluctuate. Put carbohydrates on the days that need them, and they’re less likely to become excess fat.

Q: What about vegetarian athletes?
A: Vegetarians can absolutely do dietary periodization, and carbohydrate sources are even less of an issue. The key is to be deliberate about hitting your protein target—make good use of soy products, edamame, soy milk, nuts, and whole grains, add plant-based protein supplements if needed, and watch certain micronutrients. I recommend working with a dietitian for planning.

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Conclusion: Give Your Eating a “Sense of Season” Too

Back to A-Kai. What we did afterward wasn’t complicated—we “seasonalized” his diet: during the base phase, he focused on losing weight properly while holding protein steady; the moment he entered the intensity phase, carbohydrates went straight up and fat loss stopped; before the race, he loaded according to plan. At the same race the following year, he no longer bonked in the later stages—he could even drop his rivals on the final climb. He told me: “Turns out I wasn’t undertraining—I was training on an empty body the whole time.”

At its core, dietary periodization is about putting into practice the idea that “training has seasons, and eating should have seasons too.” You don’t need to calculate to the decimal point from day one, but you should at least know: the base phase, intensity phase, race season, and off-season all demand different things from your body. If you grasp these three things—carbohydrates fluctuating with training load, protein holding the baseline, and weight adjustments timed correctly—you’re already on the right track.

Take it slow, adjust season by season, record, and observe your body’s feedback. You’ll find that once eating starts to have a sense of season, your performance will develop a rhythm of its own. Don’t chase perfection all at once. Start with the three most basic things: “more carbohydrates on big training days, pull back on rest days, and hold the protein baseline.” Even just doing this puts you ahead of the majority who only train and never think about fueling.

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This article is for educational purposes and cannot replace individual diagnosis and treatment advice from a physician, physical therapist, or dietitian. All values mentioned are general ranges for directional reference; actual intake should be individualized based on body weight, training load, health status, and professional recommendations. Those with chronic conditions must consult their primary care physician before adjusting their diet.

References

• The Basics of Carbohydrate Periodization for Athletes and Coaches — https://biomedres.us/fulltexts/BJSTR.MS.ID.006789.php
• Dietary Carbohydrate And The Endurance Athlete: Contemporary Perspectives（Gatorade Sports Science Institute）— https://www.gssiweb.org/sports-science-exchange/article/dietary-carbohydrate-and-the-endurance-athlete-contemporary-perspectives
• A Periodized Approach to Carbohydrate Intake During Training and Racing（TrainingPeaks）— https://www.trainingpeaks.com/blog/carbohydrate-intake-training-racing/
• International Society of Sports Nutrition Position Stand: Protein and Exercise — https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477153/

Related Reading

• Periodized Nutrition: Advanced Strategies to Perfectly Sync Diet with Your Training Plan
• Carbohydrate Periodization: Eat More When You Train More, Eat Less When You Train Less
• Carbohydrate Periodization: Dietary Differences Between Training Days and Rest Days
• The Complete Guide to Carbohydrate Periodization: Aligning Carbs with Training Demands—Benefits, How to Structure It, and Red Lines You Must Never Cross