REVERFIT
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For gyms
Reverfit for gymsReverfit for boxesPricingWhat's included
Management softwareMember appDiet appWorkout appFor your kind of gym
Flat price, no per-member feesBoxes and functional trainingCombat sports and martial artsPersonal trainersPilates and yoga studiosGetting ready for a station raceMore
FAQGuides for gym owners
How to collect your gym's membership feesHow much gym software costsHow to switch gym software without losing anythingHow to reduce cancellations at your gymWhat to do when a member doesn't payData protection at your gymTry it free for 7 daysFree
Calculators
All calculatorsCalories and macrosBody mass index (BMI)One-rep maxHYROX races
HYROX time calculatorHYROX splits calculatorHYROX weightsGuides
Intermittent fasting: what the evidence showsHow much protein per dayThe ketogenic diet: what the studies sayCalories to lose fat without losing muscleHow many sets per muscle per weekCreatine: what the evidence showsExercises, step by step
All exercisesBarbell squatPush-upsBench pressDeadliftPull-upsOverhead pressGuides
Clear answers
with their source
The short answer first and the explanation after, with a link to the law, the official source or the study behind every figure. Written by a personal trainer and gym owner with more than 35 years of experience.
For gym owners
- How to collect your gym's membership fees. SEPA direct debit step by step, the 14-day notice, the 8-week refunds, cards, cash, and what Spanish law says about cancellations and fee increases.
- How much gym software costs. The prices each program publishes in 2026, the three ways they charge (per member, per gym or by quote) and what the price leaves out: the app with your brand, the fees and the migration.
- How to switch gym software without losing anything. What to ask your current program for before you leave, what data to take with you (members, fees, payments, photos and SEPA mandates) and how to switch without interrupting payments.
- How to reduce cancellations at your gym. How many members leave each year, why the first three months decide almost everything and what really keeps them: habit, a friend inside and staff who talk to them. With the source of every figure.
- What to do when a member doesn't pay. Talk first and then claim in writing, the five years you have to claim, the Spanish small-claims payment procedure without a lawyer, debtor registers, surcharges and what you can't do. With the article behind every point.
- Data protection at your gym. Fingerprint and facial recognition at the entrance, cameras, health data, minors, photos on social media and WhatsApp promotions, with the real fines the Spanish Data Protection Agency has imposed on gyms.
Nutrition and training
- Intermittent fasting: what the evidence shows. How much weight it takes off compared with a normal diet, what happens to blood sugar and muscle, what is not proven (autophagy, longevity) and who should not do it. With a link to every study.
- How much protein per day. The minimum (0.83 g/kg), how much to build muscle (≈1.6 g/kg), to lose fat and as you get older, whether it is bad for your kidneys, and animal versus plant protein. With a link to every study.
- The ketogenic diet: what the studies say. How many carbs a day (20-50 g) and what happens if you eat them all in one meal, how much weight is lost compared with other diets, what happens to cholesterol and diabetes, whether protein kicks you out of ketosis and who should not do it. With a link to every study.
- Calories to lose fat without losing muscle. How to estimate what you burn, which deficit best preserves lean mass, why the 7,700 kcal per kilo rule fails, whether your metabolism slows down and the minimum calories. With a link to every study.
- How many sets per muscle per week. How many sets to build muscle (10 or more) or strength, whether you need to train to failure, once or twice a week, how long to rest and the minimum for health. With a link to every study.
- Creatine: what the evidence shows. Strength, muscle mass, older adults and women, the doses studied, whether it is safe for your kidneys and your hair, and the claims EU law allows. With a link to every study.
And the software to run it all?
Members, fees, bookings and access control, at a fixed price per gym. The dashboard is in English.
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