[{"data":1,"prerenderedAt":660},["ShallowReactive",2],{"lexique-en-lean-mass":3,"lexique-all-en":302,"lexique-trans-en-lean-mass":655},{"id":4,"title":5,"body":6,"description":292,"extension":293,"lang":294,"letter":295,"meta":296,"navigation":297,"path":298,"ref":12,"seo":299,"stem":300,"__hash__":301},"lexique/lexique/en/lean-mass.md","Lean mass",{"type":7,"value":8,"toc":280},"minimark",[9,13,18,31,34,37,40,45,97,99,103,144,146,150,153,166,169,180,182,186,218,220,224,227,238,240,243,245,249,263,265,269],[10,11,5],"h1",{"id":12},"lean-mass",[14,15,17],"h4",{"id":16},"definition","Definition",[19,20,21,22,26,27,30],"p",{},"The ",[23,24,25],"strong",{},"lean mass"," (or fat-free mass, FFM) is the ",[23,28,29],{},"total weight of all your body tissues except fat",". It includes muscles, bones, organs, water, blood, connective tissues.",[32,33],"blockquote",{},[19,35,36],{},"💡 Total weight = lean mass + fat mass. They're the two complementary halves of body composition.",[38,39],"hr",{},[41,42,44],"h3",{"id":43},"whats-inside-lean-mass","What's inside lean mass?",[46,47,48,61],"table",{},[49,50,51],"thead",{},[52,53,54,58],"tr",{},[55,56,57],"th",{},"Component",[55,59,60],{},"% of lean mass",[62,63,64,73,81,89],"tbody",{},[52,65,66,70],{},[67,68,69],"td",{},"Skeletal muscles",[67,71,72],{},"40-50%",[52,74,75,78],{},[67,76,77],{},"Body water",[67,79,80],{},"30-40%",[52,82,83,86],{},[67,84,85],{},"Bones",[67,87,88],{},"15-20%",[52,90,91,94],{},[67,92,93],{},"Organs and other tissues",[67,95,96],{},"10-15%",[38,98],{},[41,100,102],{"id":101},"why-is-lean-mass-crucial","Why is lean mass crucial?",[104,105,106,114,120,126,132,138],"ul",{},[107,108,109,110,113],"li",{},"✅ ",[23,111,112],{},"Higher metabolism",": lean mass largely determines BMR",[107,115,109,116,119],{},[23,117,118],{},"Functional strength",": more muscle = more force",[107,121,109,122,125],{},[23,123,124],{},"Strong skeleton",": bones reinforced by training",[107,127,109,128,131],{},[23,129,130],{},"Reduced injury risk",": stable joints",[107,133,109,134,137],{},[23,135,136],{},"Longevity",": studies link lean mass to lower mortality",[107,139,109,140,143],{},[23,141,142],{},"Aesthetics",": athletic, full silhouette",[38,145],{},[41,147,149],{"id":148},"lean-mass-vs-muscle-mass","Lean mass vs muscle mass",[19,151,152],{},"Don't confuse the two:",[104,154,155,161],{},[107,156,157,160],{},[23,158,159],{},"Muscle mass",": skeletal muscles ONLY",[107,162,163,165],{},[23,164,5],{},": muscles + bones + organs + water + everything except fat",[19,167,168],{},"For an 80 kg adult man:",[104,170,171,174,177],{},[107,172,173],{},"Lean mass: ~65 kg (81%)",[107,175,176],{},"Skeletal muscles: ~32 kg (40%)",[107,178,179],{},"Fat mass: ~15 kg (19%)",[38,181],{},[41,183,185],{"id":184},"how-to-gain-lean-mass","How to gain lean mass",[104,187,188,194,200,206,212],{},[107,189,109,190,193],{},[23,191,192],{},"Heavy strength training",": 3-5x/week",[107,195,109,196,199],{},[23,197,198],{},"Sufficient protein",": 1.6-2.2 g/kg",[107,201,109,202,205],{},[23,203,204],{},"Caloric surplus",": +200-400 kcal/day",[107,207,109,208,211],{},[23,209,210],{},"Adequate hydration",": water = ~30% of lean mass",[107,213,109,214,217],{},[23,215,216],{},"Quality sleep",": 7-9h for hormonal recovery",[38,219],{},[41,221,223],{"id":222},"watch-out-for-water-variations","Watch out for water variations",[19,225,226],{},"Lean mass measurements (especially bioimpedance) are highly affected by hydration:",[104,228,229,232,235],{},[107,230,231],{},"Dehydrated → lean mass reads low",[107,233,234],{},"Just after eating salty foods → lean mass reads high (water retention)",[107,236,237],{},"Just after intense workout → distorted readings",[32,239],{},[19,241,242],{},"⚠️ Always measure under the same conditions: morning, fasted, after bathroom, before drinking.",[38,244],{},[41,246,248],{"id":247},"common-mistakes","Common mistakes",[104,250,251,254,257,260],{},[107,252,253],{},"❌ Confusing lean mass and muscle mass",[107,255,256],{},"❌ Trusting bioimpedance readings without controlling conditions",[107,258,259],{},"❌ Sacrificing lean mass during aggressive cuts",[107,261,262],{},"❌ Stopping strength training when getting older",[38,264],{},[41,266,268],{"id":267},"key-takeaways","Key takeaways",[19,270,271,272,275,276,279],{},"Lean mass is ",[23,273,274],{},"everything except fat in your body",". Build it (heavy training + protein + surplus), protect it (controlled cut, never aggressive), and track it under stable conditions. ",[23,277,278],{},"Optimal lean mass = solid foundation for life",".",{"title":281,"searchDepth":282,"depth":282,"links":283},"",2,[284,286,287,288,289,290,291],{"id":43,"depth":285,"text":44},3,{"id":101,"depth":285,"text":102},{"id":148,"depth":285,"text":149},{"id":184,"depth":285,"text":185},{"id":222,"depth":285,"text":223},{"id":247,"depth":285,"text":248},{"id":267,"depth":285,"text":268},"Lean mass is everything in your body except fat: muscles, bones, organs, water. A real performance indicator.","md","en","L",{},true,"/lexique/en/lean-mass",{"title":5,"description":292},"lexique/en/lean-mass","1DFibcPq-z_2tgzTIE5ydV8XDrR0lNRgiiKkzeyQHFc",[303,307,311,315,319,323,327,331,335,339,343,347,351,355,359,363,367,371,375,379,383,387,391,395,399,403,407,411,415,419,423,427,431,435,439,443,447,451,455,459,460,464,468,472,476,480,484,488,492,496,499,503,507,511,515,519,523,527,531,535,539,543,547,551,555,559,563,567,571,575,579,583,587,591,595,599,603,607,611,615,619,623,627,631,635,639,643,647,651],{"title":304,"description":305,"slug":306},"AMRAP - As Many Reps/Rounds As Possible","AMRAP is a high-intensity training format: do as many reps or rounds as possible in a fixed time. CrossFit favorite.","amrap-as-many-reps-rounds-as-possible",{"title":308,"description":309,"slug":310},"ATP (Adenosine Triphosphate)","ATP is the universal energy currency of the body. Every muscle contraction, every cellular function depends on it.","atp-adenosine-triphosphate",{"title":312,"description":313,"slug":314},"Abduction","Discover what abduction is in bodybuilding, this movement which moves a limb away from the central axis of the body to develop the stabilizing muscles.","abduction",{"title":316,"description":317,"slug":318},"Active recovery","Active recovery uses light activity to speed muscle recovery. Find out how to effectively integrate it into your routine.","active-recovery",{"title":320,"description":321,"slug":322},"Adduction","Adduction is a movement that brings a body part toward the body's midline. Opposite of abduction.","adduction",{"title":324,"description":325,"slug":326},"Aerobic System","The aerobic system produces energy with oxygen, fueling long-duration efforts. It's the foundation of endurance and recovery.","aerobic-system",{"title":328,"description":329,"slug":330},"Anabolic window","The anabolic window is the post-workout period considered ideal for nutrition. The reality: it's much longer than thought.","anabolic-window",{"title":332,"description":333,"slug":334},"Anaerobic System","The anaerobic system produces energy without oxygen — for explosive, intense efforts. Limited but powerful, it fuels strength and sprints.","anaerobic-system",{"title":336,"description":337,"slug":338},"BCAA","BCAAs are 3 essential branched-chain amino acids: leucine, isoleucine, valine. Discover their real usefulness, timing, and whether you actually need them.","bcaa",{"title":340,"description":341,"slug":342},"BMI","BMI (Body Mass Index) is a quick health screening tool, but it doesn't account for body composition. Limited but useful.","bmi-body-mass-index",{"title":344,"description":345,"slug":346},"BMR","BMR (Basal Metabolic Rate) is your resting metabolism — the calories burned just to stay alive. Learn how to calculate and optimize it for your fitness goals.","bmr",{"title":348,"description":349,"slug":350},"Body fat percentage","Body fat percentage measures the share of fat in your total body mass. A key indicator of body composition.","body-fat-percentage",{"title":352,"description":353,"slug":354},"Body recomposition","Body recomposition is gaining muscle and losing fat at the same time. Possible but slow — discover the conditions for success.","body-recomposition",{"title":356,"description":357,"slug":358},"Bodyweight","Bodyweight training uses your own body as resistance. No equipment, anywhere, scalable to any level.","bodyweight",{"title":360,"description":361,"slug":362},"Calorie Maintenance","Caloric maintenance is the calorie level keeping your weight stable. Foundation of any nutritional plan.","calorie-maintenance",{"title":364,"description":365,"slug":366},"Calorie Surplus","A caloric surplus means consuming more calories than you burn. Mandatory mechanism for serious muscle building.","calorie-surplus",{"title":368,"description":369,"slug":370},"Calorie deficit","A caloric deficit means consuming fewer calories than you burn. It's the only proven mechanism for fat loss. Learn how to set yours up properly.","calorie-deficit",{"title":372,"description":373,"slug":374},"Calories","Calories measure the energy provided by food. Understanding your caloric needs is the foundation of every fitness goal.","calories",{"title":376,"description":377,"slug":378},"Carbohydrates","Carbohydrates are the main source of energy for intense training. Discover your needs, the different types and their role in performance.","carbohydrates",{"title":380,"description":381,"slug":382},"Circuit training","Circuit training chains several exercises with little rest. Ideal for burning calories and improving cardiovascular fitness while keeping muscle.","circuit-training",{"title":384,"description":385,"slug":386},"Concentric (Phase)","The concentric phase is the lifting movement, where the muscle shortens under load. It's the active phase that produces force.","concentric-phase",{"title":388,"description":389,"slug":390},"Creatine","Creatine is the most studied supplement in sports nutrition, proven to boost strength, power and muscle mass. Learn dosage, timing and real benefits.","creatine",{"title":392,"description":393,"slug":394},"Cutting","A cutting phase is a period of caloric deficit aimed at losing fat while preserving muscle. Discover how to do it without losing your hard-earned gains.","dried",{"title":396,"description":397,"slug":398},"DOMS (Delayed Onset Muscle Soreness)","DOMS is the muscle soreness that appears 24-72h after exercise. Discover its causes, how to manage it, and what it really means for your progress.","doms-delayed-onset-muscle-soreness",{"title":400,"description":401,"slug":402},"Deload","Deload is an active recovery week where you intentionally reduce volume and intensity to allow your body to fully recover and come back stronger.","deload",{"title":404,"description":405,"slug":406},"Dropset","A dropset extends a set by reducing the load when failure hits. Powerful intensification method for hypertrophy.","dropset",{"title":408,"description":409,"slug":410},"EMOM - Every Minute On the Minute","EMOM (Every Minute On the Minute) is a training format where you start a set at the top of each minute and rest until the next.","emom-every-minute-on-the-minute",{"title":412,"description":413,"slug":414},"Eccentric (Phase)","The eccentric phase is the lowering movement, where the muscle lengthens under tension. It's the most damaging phase and the key driver of hypertrophy.","eccentric-phase",{"title":416,"description":417,"slug":418},"Extension","Extension is the anatomical movement that increases the angle between two body segments. Opposite of flexion.","extension",{"title":420,"description":421,"slug":422},"Fat mass","Fat mass is the total weight of fat tissue. Essential for survival, but excess harms health and aesthetics.","fat-mass",{"title":424,"description":425,"slug":426},"Fibers","Muscle fibers are the cells that make up muscle. Two main types — Type I (slow) and Type II (fast) — define your physical potential.","fibers",{"title":428,"description":429,"slug":430},"Flexion","Flexion is the anatomical movement that decreases the angle between two body segments. Opposite of extension.","flexion",{"title":432,"description":433,"slug":434},"Foam rolling","Foam rolling is a myofascial self-massage technique to release muscle tension. Find out how to use it effectively to improve recovery and mobility.","foam-rolling",{"title":436,"description":437,"slug":438},"For Time","For Time is a training format where you complete a fixed amount of work as fast as possible. Race against the clock.","for-time",{"title":440,"description":441,"slug":442},"Full Body","A full body program trains all major muscle groups in each session, 2-4 times per week. Ideal for beginners and strength training.","full-body",{"title":444,"description":445,"slug":446},"Hypertrophy","Muscle hypertrophy is the increase in muscle fiber size. It's the primary mechanism behind muscle growth from resistance training.","hypertrophy",{"title":448,"description":449,"slug":450},"Hypertrophy Training","Hypertrophy training aims to maximize muscle growth using moderate loads (65-85% 1RM) with 8-15 repetitions per set.","hypertrophy-training",{"title":452,"description":453,"slug":454},"Intra-workout","Intra-workout refers to nutrition consumed during training to maintain energy, hydration and performance on long sessions.","intra-workout",{"title":456,"description":457,"slug":458},"Isometric","Isometric contraction is when the muscle produces tension without changing length. No visible movement, intense work.","isometric-contraction",{"title":5,"description":292,"slug":12},{"title":461,"description":462,"slug":463},"Lipids (Fats)","Lipids are essential for hormone production and vitamin absorption. Discover your needs, the right sources and their role in bodybuilding.","lipids-fats",{"title":465,"description":466,"slug":467},"Macrocycle","A macrocycle is the global organization of your training over 3-12 months. The highest level of periodization, your annual game plan.","macrocycle",{"title":469,"description":470,"slug":471},"Macronutrients (Macros)","Macronutrients are the 3 main types of nutrients: proteins, carbohydrates and lipids. Their balance is crucial for performance and body composition.","macronutrients-macros",{"title":473,"description":474,"slug":475},"Maintenance","Maintenance is the calorie level at which your weight remains stable. The neutral baseline for any nutritional strategy.","maintenance",{"title":477,"description":478,"slug":479},"Mass gain","Mass gain (or bulk) is a controlled caloric surplus phase aimed at building muscle. Discover how to do it without gaining excess fat.","mass-gain",{"title":481,"description":482,"slug":483},"Meal timing","Meal timing is the strategic distribution of your meals around training and through the day to optimize performance and recovery.","meal-timing",{"title":485,"description":486,"slug":487},"Mesocycle","A mesocycle is a 4-8 week training block with a specific objective (hypertrophy, strength, peak, deload). The cornerstone of periodization.","mesocycle",{"title":489,"description":490,"slug":491},"Microcycle","A microcycle is the smallest planning unit in bodybuilding: generally 1 week of training. This is your weekly routine.","microcycle",{"title":493,"description":494,"slug":495},"Mobility","Mobility is the ability to actively control range of motion. Find out how to improve your mobility to optimize your performance.","mobility",{"title":159,"description":497,"slug":498},"Muscle mass is the total weight of muscles in the body. Key indicator of strength, metabolism, and longevity.","muscle-mass",{"title":500,"description":501,"slug":502},"Muscular Endurance Training","Muscular endurance training develops the ability to sustain prolonged effort. Light loads, high reps, short rests.","muscular-endurance-training",{"title":504,"description":505,"slug":506},"Muscular endurance","Muscular endurance is a muscle's capacity to sustain repeated or prolonged contractions without excessive fatigue. Foundation of many sports.","muscular-endurance",{"title":508,"description":509,"slug":510},"Muscular strength","Muscular strength is the maximum force a muscle (or group) can produce. The fundamental physical quality of any athlete.","muscular-strength",{"title":512,"description":513,"slug":514},"NEAT","NEAT is the energy you burn through all your daily activities outside of training. The most underestimated lever of your body composition.","neat",{"title":516,"description":517,"slug":518},"PR - Personal Record","A PR (Personal Record) is your best performance ever on a movement. The fundamental progress marker.","pr-personal-record",{"title":520,"description":521,"slug":522},"Passive recovery","Passive recovery links on complete rest to allow the body to regenerate. Find out when and how to use it effectively.","passive-recovery",{"title":524,"description":525,"slug":526},"Periodization","Periodization is the cyclical organization of training into distinct phases to optimize progression, prevent plateaus, and avoid injuries.","periodization",{"title":528,"description":529,"slug":530},"Plateau","A plateau is a period of stagnation despite consistent training. Identifying the cause is the key to breaking it.","plateau",{"title":532,"description":533,"slug":534},"Post-workout","The post-workout is the nutrition right after training to optimize recovery and growth. Protein, carbs, hydration.","post-workout",{"title":536,"description":537,"slug":538},"Pre-workout","The pre-workout is the meal or supplement taken before training to optimize performance. Energy, focus, and pump.","pre-workout",{"title":540,"description":541,"slug":542},"Progressive overload","Progressive overload is the foundational principle of training: gradually increasing the demand on your muscles to keep gaining strength and size.","progressive-overload",{"title":544,"description":545,"slug":546},"Protein","Protein is the essential macronutrient for building and repairing muscle. Discover your needs, the best sources and the optimal timing.","protein",{"title":548,"description":549,"slug":550},"Protein powder","Protein powders are concentrated protein supplements. Practical for hitting daily protein needs.","protein-powder",{"title":552,"description":553,"slug":554},"Push/Pull/Legs (PPL)","The Push/Pull/Legs program divides the workout into 3 types of sessions: push (chests/shoulders/triceps), pull (back/biceps) and legs. Optimal for all levels with frequency 2x/week per muscle.","push-pull-legs-ppl",{"title":556,"description":557,"slug":558},"RIR","RIR (Reps in Reserve) measures how many reps you have left before failure. Modern, intuitive tool to manage intensity.","rir-reps-in-reserve",{"title":560,"description":561,"slug":562},"RPE","RPE (Rate of Perceived Exertion) is a 1-10 scale to measure subjective effort. Essential tool for managing intensity.","rpe-rate-of-perceived-exertion",{"title":564,"description":565,"slug":566},"Range of motion (ROM)","Range of motion (ROM) is the amplitude through which a joint or muscle can move during an exercise. Crucial for hypertrophy and joint health.","range-of-motion-rom",{"title":568,"description":569,"slug":570},"Repetitions (Reps)","A rep is one complete execution of an exercise. The rep range determines whether you primarily develop strength, hypertrophy, or muscular endurance.","repetitions-reps",{"title":572,"description":573,"slug":574},"Rest","Rest between sets is critical and depends on the goal. Strength: 3-5 min. Hypertrophy: 1-3 min. Endurance: 30-60 sec.","rest",{"title":576,"description":577,"slug":578},"Rest-Pause","Rest-pause is an intensification method using ultra-short pauses to extend a set. Powerful tool for hypertrophy.","rest-pause",{"title":580,"description":581,"slug":582},"Sarcomere","The sarcomere is the basic contractile unit of muscle. Composed of actin and myosin, it produces all your movements.","sarcomere",{"title":584,"description":585,"slug":586},"Series (Sets)","A series (or set) is a group of consecutive reps without rest. The basic unit of training programming.","series-sets",{"title":588,"description":589,"slug":590},"Sleep","Sleep is the most underrated training variable. It's during sleep that recovery, muscle building, and hormonal regulation happen.","sleep",{"title":592,"description":593,"slug":594},"Split (Split program)","A split workout involves dividing muscle groups over different days. The classic split trains each muscle once a week for 5-6 days.","split-split-program",{"title":596,"description":597,"slug":598},"Strength Training","Strength training aims to develop maximal strength using heavy loads (80-95% of 1RM) with few repetitions (1-6 reps).","strength-training",{"title":600,"description":601,"slug":602},"Stretching","Stretching improves flexibility and range of motion. Learn about the different types and how to effectively incorporate them into your routine.","stretching",{"title":604,"description":605,"slug":606},"Superset","A superset chains two exercises with no rest between them. Time-efficient method that boosts intensity and density.","superset",{"title":608,"description":609,"slug":610},"TDEE","TDEE (Total Daily Energy Expenditure) represents your total daily energy expenditure. Find out how to calculate it precisely to optimize your results.","tdee",{"title":612,"description":613,"slug":614},"TUT - Time Under Tension","TUT (Time Under Tension) measures the total time the muscle is under load during a set. Key variable for hypertrophy.","tut-time-under-tension",{"title":616,"description":617,"slug":618},"Tabata","Tabata is a 4-minute HIIT protocol: 20 seconds max effort, 10 seconds rest, 8 rounds. Maximum efficiency in minimum time.","tabata",{"title":620,"description":621,"slug":622},"Tempo - Execution speed","Tempo is the controlled speed of each phase of a movement. Powerful tool to maximize stimulus and control.","tempo-execution-speed",{"title":624,"description":625,"slug":626},"Training density","Training density measures the amount of work done per unit of time. Increase it to boost intensity and metabolic stress.","training-density",{"title":628,"description":629,"slug":630},"Training frequency","Training frequency defines how many times per week you work a muscle. Discover the optimal frequency to progress.","training-frequency",{"title":632,"description":633,"slug":634},"Training intensity","Bodybuilding intensity measures the difficulty of the effort. Find out how to calculate it with % of 1RM, RPE, and RIR.","training-intensity",{"title":636,"description":637,"slug":638},"Training volume","Training volume represents the total amount of work performed. Discover the optimal volumes per muscle per week to progress.","training-volume",{"title":640,"description":641,"slug":642},"Type I muscle fibers","Type I fibers (slow-twitch) are endurance-oriented muscle fibers. Resistant to fatigue, they sustain prolonged efforts.","muscle-fibers-type-i",{"title":644,"description":645,"slug":646},"Type II muscle fibers","Type II fibers (fast-twitch) are powerful muscle fibers optimized for explosive efforts. Essential for strength and power.","type-ii-muscle-fibers",{"title":648,"description":649,"slug":650},"Upper/Lower","The Upper/Lower program divides training into upper body and lower body sessions over 4 days per week. Perfect balance between frequency (2x/week) and volume for all levels.","upper-lower",{"title":652,"description":653,"slug":654},"VO2 max","VO2 max is the maximum amount of oxygen your body can use during intense exercise. It's the gold standard of cardiovascular fitness.","vo2-max",{"de":656,"en":12,"es":657,"fr":658,"it":659,"pt":659},"magermasse","masa-magra","masse-maigre","massa-magra",1784214982376]