[UPDATED PROGRAMMING - MARCH 22, 2024]
Are you tired of tirelessly working out, only to see little to no progress in your physique? Don't worry, you're not alone.
Building lean muscle can seem like a challenging task, but with the right approach, it's entirely achievable. In this comprehensive Fit Results Guide, we'll take you on a journey to unlock the secrets of building that lean, sculpted body you've always desired.
With tips on nutrition, workouts tailored for lean muscle growth, and strategies to track your progress and make adjustments, you'll soon be well on your way to building lean muscle.
So, grab your gym gear and get ready to dive into a world of fitness wisdom that will transform your body and your life.
Understanding Lean Muscle
Lean muscle refers to the body's muscular tissue with low-fat content, giving it a firm and toned appearance.
Achieving lean muscle requires a blend of resistance training, proper nutrition, and ample rest, resulting in enhanced strength, endurance, and overall physical performance.
Difference Between Lean Muscle And Bulk Muscle
Lean muscle and bulk muscle vary mainly in appearance, training approach, and nutritional needs.
Appearance: Lean muscle boasts a toned, defined look with lower body fat levels, while bulk muscle may appear larger due to a mix of increased muscle mass and higher body fat levels.
Training approach: Building lean muscle usually involves combining compound and isolation exercises, emphasizing moderate to high repetitions and proper form. In contrast, bulking often focuses on heavy lifting and low repetitions to promote muscle size and strength gains.
Nutritional needs: Developing lean muscle necessitates a balanced diet with a slight caloric surplus, prioritizing protein intake for muscle repair and growth while managing carbohydrate and fat intake to minimize fat accumulation.
Bulking, on the other hand, often involves consuming a significant caloric surplus to support muscle growth, which may lead to increased fat gain alongside muscle mass.
Factors Affecting Lean Muscle Growth
Genetics: Genetics plays a substantial role in determining a person's natural muscle-building potential. Aspects such as muscle fiber type, hormone levels, and metabolism can impact how quickly and easily one can build lean muscle. (1)
Age: With age, hormonal changes, decreased muscle protein synthesis, and a slower metabolism can make building and maintaining lean muscle more challenging. (2) However, resistance training and proper nutrition can help counteract these effects and promote healthy aging.
Hormonal balance: Hormones like testosterone, growth hormone, and insulin-like growth factor-1 (IGF-1) play crucial roles in muscle growth and repair. Imbalances in these hormones can hinder lean muscle development. (3)
Sleep: Ensuring sufficient sleep, managing stress, and maintaining a balanced diet can help optimize hormonal balance for muscle growth.
Training program: A well-crafted training program incorporating progressive overload, exercise variation, and adequate rest is essential for stimulating muscle growth and preventing plateaus.
Nutrition: Consuming a balanced diet with sufficient protein, carbohydrates, and healthy fats is crucial for providing the nutrients needed for muscle repair, growth, and energy during workouts.
Recovery: Sufficient rest and recovery are vital for allowing the body to repair and grow muscle tissue. Overtraining and insufficient sleep can impair muscle recovery and growth, further emphasizing the importance of rest days and proper sleep hygiene. (4)
Stress levels: Chronic stress can negatively impact muscle growth by increasing cortisol levels, which can hinder muscle protein synthesis and promote muscle breakdown. Managing stress through relaxation techniques, regular exercise, and a balanced diet can help optimize lean muscle development.
Nutrition for Lean Muscle Growth
Alright, let's talk about something crucial for building lean muscle - food! You can't expect to see any results if you're not fueling your body with the right nutrients. Here is a breakdown of everything you need to know about nutrition for building lean muscle.
Importance Of Proper Nutrition
Proper nutrition is the foundation for lean muscle growth. A well-balanced diet provides the essential nutrients, vitamins, and minerals needed to fuel workouts, recover from exercise, and support muscle growth.
Without adequate nutrition, your body will struggle to repair and build muscle tissue, hindering your progress and potentially leading to injury or burnout.
Macronutrient Ratios
Protein: Protein is your muscle's best friend, providing essential amino acids that help repair and grow muscle tissue. According to ACSM (American College for Sports Medicine), you should aim for 1.2-1.7 grams of protein per kilogram of body weight daily, depending on your activity level and specific goals.
Get your protein fix from lean meats, fish, dairy, eggs, or plant-based heroes like beans, lentils, and tofu.
Carbohydrates: Carbs are your body's go-to fuel during workouts, giving you the energy you need to shine.
A generous helping of carbohydrates empowers your body to push its limits, leading to lean muscle growth. Consuming 1.2 - 1.5 g of carbs per 2.2 lbs of your body weight is recommended.(5) As an example, if you weigh 180 pounds, you should consume 270 g of carbs each day.
Opt for complex carbs like whole grains, fruits, and veggies, which offer lasting energy and essential nutrients.
Fats: Healthy fats are vital for overall health, hormone production, and energy. Strive for a balance of monounsaturated and polyunsaturated fats from sources such as avocados, nuts, seeds, and olive oil. Fats should make up about 20-35% of your daily calorie intake.
Micronutrients And Their Role
While macronutrients like carbohydrates, proteins, and fats provide the body with energy, micronutrients are essential for regulating various bodily functions and maintaining good health.
Lean muscle growth's micronutrient superstars include vitamin D, calcium, magnesium, and zinc. Each of these micronutrients plays a distinct role in muscle function and development:
Vitamin D: Vitamin D is a vital player in calcium absorption and bone health, but it doesn't stop there. It moonlights muscle function, with research showing that vitamin D deficiency can lead to muscle weakness and atrophy (8).
Calcium: Calcium is the life of the muscle contraction party, playing a massive role in muscle growth and strength. Getting enough calcium is crucial for supporting bone health, which in turn allows for proper muscle function and lowers the risk of injury (9).
Magnesium: Involved in over 300 enzymatic reactions, magnesium is a true multitasker. It's a key player in energy production and muscle function, helping muscles relax and keeping cramps at bay. (10).
Zinc: Zinc is needed in small amounts, but it packs a punch. This essential trace element has its hands in all aspects of cellular metabolism, from protein synthesis and cell division to DNA synthesis. It's a critical ally for muscle repair, growth, and a robust immune system (11).
Make sure your diet is bursting with a colorful mix of fruits, vegetables, whole grains, and lean proteins to meet your micronutrient needs.
Supplements For Lean Muscle Growth
Protein powder: Protein powder is a hassle-free and effective way to amp up your daily protein consumption.
Blend it into smoothies, stir it into oatmeal, or simply mix it with water or milk. Opt for top-quality protein sources such as whey, casein, or plant-based alternatives like pea or rice protein.
Creatine: Creatine has been shown to enhance muscle strength, power, and size when paired with resistance training. (6)
It works its magic by increasing phosphocreatine availability, which fuels energy production during high-intensity workouts.
Branched-chain amino acids (BCAAs): BCAAs comprise three vital amino acids (leucine, isoleucine, and valine) that contribute to muscle protein synthesis and recovery.
Supplementing with BCAAs may help ease muscle soreness and bolster lean muscle growth, especially when taken before or after exercise sessions. (7)
Importance Of Hydration
Staying hydrated is crucial for overall health, workout performance, and muscle recovery.
Water helps transport nutrients to your muscles, aids in digestion, and supports the removal of waste products.
Aim to drink at least half an ounce of water for every pound of body weight daily. So, if you tip the scales at 150 pounds, make sure to drink at least 75 ounces of water each day.
However, this number can also vary depending on the weather and your overall activity level.
Sample Meal Plan For Lean Muscle Growth
Please note that this meal plan and the nutritional values provided are just estimations and may not suit everyone's dietary preferences or nutritional requirements. For a customized diet plan tailored to your specific needs and goals, consult a registered dietitian or nutritionist.
Having said that, here's a sample meal plan based on a 2000-kcal intake.
Best Workouts for Lean Muscle Growth
Let's go over both compound and isolation exercises and their benefits, as well as some examples you can add to your workout routine.
Compound Exercises
Compound exercises are multi-joint movements that involve the use of multiple muscle groups and joints simultaneously.
These exercises provide a multitude of benefits for those seeking lean muscle growth.
By engaging multiple muscle groups simultaneously, these exercises maximize your workout efficiency, allowing you to target more muscles in less time.
This leads to an increased calorie burn both during and after your workout, which aids in fat loss and helps reveal your lean muscle gains.
Furthermore, compound exercises closely mimic everyday functional movements and sports-specific activities, enhancing your overall athletic performance and reducing the risk of injury.
Examples:
- Squats: An all-time favorite for lower body strength, squats engage your quads, hamstrings, glutes, and core muscles.
- Deadlifts: This powerhouse exercise targets your posterior chain, working the hamstrings, glutes, lower back, and even your lats and traps.
- Bench presses A classic upper body exercise, bench presses work your chest, shoulders, and triceps.
- Pull-ups: Pull-ups primarily target your lats, while also engaging your biceps, forearms, and core.
- Rows: Whether performed with dumbbells, a barbell, or a cable machine, rows effectively work your back muscles and biceps.
- Overhead presses: This compound movement targets your shoulders, triceps, and core muscles.
Isolation Exercises
While compound exercises are the backbone of any lean muscle-building program, isolation exercises also have a place in your routine.
These exercises focus on a single muscle group, allowing you to fine-tune specific areas that may need extra attention or development.
Incorporating isolation exercises can help correct muscle imbalances, enhance muscle definition, and assist in injury prevention and rehabilitation.
Examples:
- Bicep curls: Using dumbbells, a barbell, or a cable machine, these exercises isolate and strengthen the biceps brachii.
- Tricep extensions: Performed with dumbbells, a cable machine, or a resistance band, tricep extensions work the triceps brachii.
- Leg curls: Leg curls isolate the hamstrings, working them through a full range of motion.
- Calf raises: This isolation exercise specifically targets the gastrocnemius and the soleus muscles in the calves, which are often neglected in compound movements.
- Lateral raises: Performed with dumbbells or a cable machine, lateral raises isolate the lateral deltoid muscles in the shoulders.
- Hamstring curls: Using a leg curl machine or a stability ball, hamstring curls focus on the semitendinosus, semimembranosus, and biceps femoris.
Workout Frequency And Intensity
To effectively stimulate lean muscle growth, it's important to strike the right balance between workout frequency and intensity.
Aim to exercise each muscle group 2-3 times per week, with at least 48 hours of rest between sessions targeting the same muscle group. This allows for optimal muscle recovery and growth.
Vary the intensity of your workouts by incorporating a mix of low-rep, high-weight sessions to build strength and high-rep, low-weight sessions to improve endurance and muscle tone.
Additionally, consider incorporating supersets or drop sets to further challenge your muscles and maximize your time in the gym.
Supersets pair two exercises together, performed back-to-back with minimal rest in between.
You can either work for the same muscle group (think bicep curls followed by hammer curls) or target opposing muscle groups (like bench press followed by bent-over rows).
Not only do supersets save time, but they also crank up the intensity and help your muscles grow.
On the flip side, drop sets are all about pushing your muscles to the limit.
Start by lifting a heavy weight until muscle failure, then immediately lower the weight and continue the exercise until failure once more. You can repeat this process multiple times, dropping the weight with each round.
For example, you could do bicep curls with a 30-pound dumbbell, switch to a 20-pound one, and wrap up with a 10-pounder. Drop sets boost muscle endurance and trigger growth by thoroughly exhausting your muscle fibers.
Incorporating both supersets and drop sets into your routine can lead to improved muscle growth, strength, and endurance, all while making your workouts more time-efficient.
Workout Splits
Upper/lower split: The upper/lower split divides your workouts into separate upper-body and lower-body sessions.
This approach allows you to focus on each muscle group with greater intensity, while still providing adequate rest and recovery time between sessions.
An example of this split might involve training the upper body on Monday and Thursday, and the lower body on Tuesday and Friday.
Push/pull/legs split: This popular split organizes workouts based on the primary movement patterns: pushing, pulling, and leg exercises.
Push exercises primarily target the chest, shoulders, and triceps; pull exercises focus on the back and biceps; and leg exercises work the lower body.
This split is highly customizable and can be tailored to suit individual needs and goals. For example, you might follow a push/pull/legs routine on Monday, Wednesday, and Friday, with rest or active recovery days in between.
Full-body workout: Full-body workouts involve training all major muscle groups in a single session. This approach is ideal for those with limited time, beginners, or those looking to improve overall fitness and functional strength.
A full-body workout might include 2-3 compound exercises for each major muscle group, with additional isolation exercises as needed.
Full-body workouts can be performed 2-3 times per week, with at least 48 hours of rest between sessions.
We go through variations of each split in this 4 week program to get you used to the basics.
Rest And Recovery
Allowing your muscles adequate time to recover is essential for lean muscle growth. Aim for at least 48 hours of rest between training the same muscle group and prioritize sleep, as it is vital for muscle repair and growth. Aim for 7-9 hours of quality sleep per night to optimize recovery.
Incorporate active recovery techniques such as foam rolling, stretching, and light cardio to maintain mobility and promote blood flow to the muscles.
These activities can help reduce muscle soreness and expedite the recovery process.
Four Week Lean Muscle Routine
Here is a 4-week push/pull/legs workout plan that alternates between a mixture of compound exercise.
Bear in mind, that this workout plan is just a starting point and may not be the perfect match for everyone.
After all, everyone is unique, with different goals, physical abilities, and wellness considerations. That's why it's essential to have a chat with your personal trainer before diving into any workout plan.
Week 1
Monday - Full Body (Compound Focus)
- Squats: 3 sets of 12 reps
- Bench Press: 3 sets of 12 reps
- Deadlifts: 3 sets of 12 reps
- Pull-Ups (or Assisted Pull-Ups): 3 sets of 10 reps
- Planks: 3 sets of 60 seconds
Tuesday: Active Recovery
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Wednesday - Upper Body (Isolation Focus)
- Dumbbell Bicep Curls: 4 x 15 reps
- Tricep Dips: 4 x 15 reps
- Lateral Raises: 4 x 15 reps
- Face Pulls: 4 x 15 reps
Thursday - Active Recovery
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Friday - Lower Body (Isolation Focus)
- Leg Extensions: 4 x 15 reps
- Hamstring Curls: 4 x 15 reps
- Single Leg Calf Raises: 4 x 20 reps each side
- Bulgarian Split Squats: 3 x 12 reps on each leg
Saturday - Full Body (Mixed)
- Lunges: 3 x 12 reps per leg
- Incline Dumbbell Press: 3 x 12 reps
- Bent-Over Dumbell Rows: 3 x 12 reps
- Russian Twists: 3 x 15 reps per side
Sunday - Rest
- (Optional) Stretching and Foam Rolling: 15 minutes
Week 2 Progressive Overload
Monday - Upper Body
- Bench Press: 4 x 8 reps
- Bent-Over Barbell Rows: 4 x 8 reps
- Overhead Press: 4 x 8 reps
- Chin-Ups: 3 x 8 reps
Tuesday - Lower Body
- Squats: 4 x 8 reps
- Deadlifts: 4 x 8 reps
- Leg Press: 3 x 10 reps
- Calf Raises: 3 x 15 reps
Wednesday - Active Recovery
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Thursday - Full Body
- Incline Dumbbell Press: 3 x 10 reps
- Lunges: 3 x 10 reps per leg
- Lat Pulldowns: 3 x 10 reps
- Cable Tricep Extensions: 3 x 12 reps
- Bicep Curls: 3 x 10 reps
Friday - Active Recovery
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Saturday - Full Body (Compound Focus)
- Squats: 4 x 8 reps
- Bench Press: 4 x 8 reps
- Deadlifts: 4 x 8 reps
- Pull-Ups (or Assisted Pull-Ups): 3 x 8 reps
- Planks: 3 x 60 seconds
Sunday - Rest
- (Optional) Stretching and Foam Rolling: 15 minutes
Week 3 - Increasing Intensity
Monday - Push Day
- Bench Press: 4 x 6 reps
- Overhead Press: 4 x 6 reps
- Dips: 3 x 8 reps
- Tricep Pushdowns: 3 x 10 reps
Tuesday - Pull Day
- Deadlifts: 4 x 6 reps
- Pull-Ups: 4 x 6 reps
- Bent-Over Barbell Rows: 3 x 8 reps
- Bicep Curls: 3 x 10 reps
Wednesday - Active Recovery or Rest
Thursday - Leg Day
- Squats: 4 x 6 reps
- Romanian Deadlifts: 4 x 6 reps
- Leg Press: 3 x 8 reps
- Seated Calf Raises: 3 x 12 reps
Friday - Active Recovery or Rest
Saturday - Full Body (Mixed)
- Kettlebell Swings: 3 x 15 reps
- Push-Ups: 3 x 15 reps
- Step-Ups: 3 x 12 reps per leg
- Core Circuit (Planks, Russian Twists, Leg Raises) - 2 x 60 seconds each
Sunday - Rest
Week 4 - Burn & Tone
Monday - Upper Body High Volume
- Bench Press: 4 x 15-20 reps
- Dumbbell Flyes: 4 x 15-20 reps
- Lat Pulldowns: 4 x 15-20 reps
- Incline Dumbbell Press: 4 x 15-20 reps
- Lateral Raises: 3 x 20 reps
Tuesday - Lower Body High Volume
- Squats: 4 x 20 reps
- Walking Lunges: 4 x 20 reps per leg
- Leg Extensions: 4 x 20 reps
- Leg Curls: 4 x 20 reps
- Calf Raises: 5 x 20 reps
Wednesday - Active Recovery
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Thursday - Full Body Circuit (REPEAT 3X)
- Light Squats: 15 reps
- Push-Ups: 15 reps
- Bent-Over Dumbbell Rows: 15 reps
- Plank: 60 seconds
- Jump Rope: 60 seconds
Friday - Upper Body High Volume
- Pull-Ups (or Assisted Pull-Ups): 4 x 10-15 reps
- Bicep Curls: 4 x 15-20 reps
- Tricep Dips (or Tricep Pushdowns): 4 x 15-20 reps
- Face Pulls: 4 x 15-20 reps
- Crunches: 3 x 20 reps
Saturday - Lower Body High Volume
- Squats (Bodyweight or Light Barbell): 4 x 20 reps
- Stiff-Legged Deadlifts (Light Weight): 4 x 20 reps
- Step-Ups: 4 x 15 reps per leg
- Seated Calf Raises: 5 x 20 reps
- Hanging Knee Raises: 4 x 15 reps
Sunday - Rest or Light Activity
- Light Cardio (e.g., brisk walking): 30 minutes
- (Optional) Stretching and Foam Rolling: 15 minutes
Tracking Progress and Making Adjustments
Tracking progress is crucial for your fitness journey. Let's take a look at methods, signs, when to make adjustments, and tips on implementing them.
Importance Of Monitoring Progress
Monitoring your progress is essential for staying motivated and ensuring that you're on the right path toward achieving your lean muscle goals.
Regularly tracking your progress will help you identify areas for improvement, celebrate your achievements, and make necessary adjustments to your training and nutrition plan.
Methods For Tracking Progress
Body Measurements: Measure your chest, waist, hips, thighs, and arms regularly to monitor changes in your muscle size and body composition. Taking measurements every 4-6 weeks is a reliable way to track your progress over time.
Body fat percentage: Measuring your body fat percentage using methods like bioelectrical impedance analysis (BIA), skinfold calipers, or DEXA scans can provide insights into your body composition changes.
Decreasing body fat while maintaining or increasing muscle mass is a clear indicator of lean muscle growth.
Progress photos: Taking regular progress photos, preferably in the same lighting and at the same time of day, can help you visually assess your muscle development and overall physique changes.
Signs Of Progress
Increased strength: As those lean muscles take shape, you're bound to feel a surge in strength, letting you hoist heftier weights or tackle extra reps. Keep track on your performance in each exercise to measure your progress.
Improved muscle definition: When you lose body fat and gain muscle mass, you'll begin to spot more defined muscles and better muscle separation. This is a telltale sign that your training and nutrition game plan is hitting the mark.
Better overall fitness: Building lean muscle paves the way for enhanced cardiovascular endurance, flexibility, and functional strength, turning everyday activities into a breeze and boosting your overall enjoyment.
When To Make Adjustments
Plateaus: If you find that your progress has stalled for 2-3 weeks, it may be time to make adjustments to your training or nutrition plan to break through the plateau and continue progressing.
Overtraining: If you're experiencing symptoms of overtraining, such as persistent fatigue, decreased performance, or prolonged muscle soreness, consider adjusting your workout frequency, intensity, or recovery periods to give your body adequate time to recuperate.
Lack of progress: If you're not seeing the results you desire after several weeks of consistent effort, reassess your training and nutrition strategies to determine where adjustments can be made.
Tips for Making Adjustments
Changing exercises: To keep your muscles challenged and prevent adaptation, switch up your exercises every 4-6 weeks.
Incorporate different compound and isolation movements or vary the angles, grips, and equipment used to target your muscles from new angles.
Modifying workout frequency or intensity: Alter the number of workouts per week, sets, reps, or rest periods to optimize muscle growth. You may also experiment with training techniques like drop sets, supersets, or rest-pause sets to increase training intensity.
Adjusting nutrition plan: If you're not seeing the desired progress, reassess your caloric intake and macronutrient ratios.
Ensure you're consuming adequate protein, carbohydrates, and healthy fats to support muscle growth and recovery while maintaining a slight calorie surplus to facilitate muscle gain without excessive fat accumulation.
Conclusion
Well, there you have it, your complete guide to building lean muscle We hope you found these tips helpful and inspiring as you embark on your lean muscle journey.
As you forge ahead, remember to stay consistent, be patient, and most importantly, enjoy the process.
If you'd like more hands-on, beginner-friendly guidance from our expert coaches to start your lean muscle journey, check out our Get Fit Challenge.
References
1. Roth SM. Genetic aspects of skeletal muscle strength and mass with relevance to sarcopenia. Bonekey Rep. 2012;1:58. Published 2012 Apr 4. doi:10.1038/bonekey.2012.58
2. Volpi E, Nazemi R, Fujita S. Muscle tissue changes with aging. Curr Opin Clin Nutr Metab Care. 2004;7(4):405-410. doi:10.1097/01.mco.0000134362.76653.b2
3. Kraemer WJ, Ratamess NA, Hymer WC, Nindl BC, Fragala MS. Growth Hormone(s), Testosterone, Insulin-Like Growth Factors, and Cortisol: Roles and Integration for Cellular Development and Growth With Exercise. Front Endocrinol (Lausanne). 2020;11:33. Published 2020 Feb 25. doi:10.3389/fendo.2020.00033
4. Vitale KC, Owens R, Hopkins SR, Malhotra A. Sleep Hygiene for Optimizing Recovery in Athletes: Review and Recommendations. Int J Sports Med. 2019;40(8):535-543. doi:10.1055/a-0905-3103
5. Ivy JL. Regulation of muscle glycogen repletion, muscle protein synthesis and repair following exercise. J Sports Sci Med. 2004;3(3):131-138. Published 2004 Sep 1.
6. Mills S, Candow DG, Forbes SC, Neary JP, Ormsbee MJ, Antonio J. Effects of Creatine Supplementation during Resistance Training Sessions in Physically Active Young Adults. Nutrients. 2020;12(6):1880. Published 2020 Jun 24. doi:10.3390/nu12061880
7. Weber MG, Dias SS, de Angelis TR, et al. The use of BCAA to decrease delayed-onset muscle soreness after a single bout of exercise: a systematic review and meta-analysis. Amino Acids. 2021;53(11):1663-1678. doi:10.1007/s00726-021-03089-2
8. Ceglia L. Vitamin D and its role in skeletal muscle. Curr Opin Clin Nutr Metab Care. 2009;12(6):628-633. doi:10.1097/MCO.0b013e328331c707
9. Weaver CM, Gordon CM, Janz KF, et al. The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations [published correction appears in Osteoporos Int. 2016 Apr;27(4):1387]. Osteoporos Int. 2016;27(4):1281-1386. doi:10.1007/s00198-015-3440-3
10. Nielsen FH, Lukaski HC. Update on the relationship between magnesium and exercise. Magnes Res. 2006;19(3):180-189.
11. Haase H, Maret W. Intracellular zinc fluctuations modulate protein tyrosine phosphatase activity in insulin/insulin-like growth factor-1 signaling. Exp Cell Res. 2003;291(2):289-298. doi:10.1016/s0014-4827(03)00406-3
