Muscle Hypertrophy, Strength and Power: The Keys for Thriving in Midlife
Tools for the resistance training toolbox
Resistance training involves applying load to the muscles and bones by systematically manipulating variables such as the amount of load or weight, repetition range, the volume of repetitions, frequency, rest periods, exercise selection, the order in which the exercises are performed, and the velocity of muscle actions.
The benefits of resistance training for mid-life women are becoming more well-known and include the maintenance of muscle and bone mass, metabolism, and increased physical self-confidence and vitality, to name a few. When we discuss resistance training, some say that training with high repetitions with low weight is best - others promote heavy weights with fewer repetitions. The truth is that both are important! We can achieve increases in muscle strength, mass, and power through a wide variety of training paradigms.
Hypertrophy, Strength, and Power
Building muscle mass (hypertrophy) and building muscle strength are not the same thing. Hypertrophy refers to the mass or size of the muscles. Strength refers to the amount of load or weight that can be moved. Muscle power is the amount of load that can be moved in a given time period. All of these elements are important for muscle and bone health, athletic performance, and longevity and require variations in training to achieve all three.
In midlife - particularly at the time of menopause - females experience a decline in muscle mass and power due to declining circulating estrogen and tissue estrogen receptors that result in loss of muscle mass, a shift from fast-twitch type II skeletal muscle fibers (power-generating fibers) to slow-twitch type I fibers (endurance fibers) and reduced efficiency of the muscle cells to generate energy for contraction and for cellular repair.
These changes in skeletal muscle also impact metabolism. Skeletal muscle is the body’s second highest utilizer of blood glucose, second only to the brain. With the decline in muscle mass, the hormone, insulin, needs to work harder to help the muscles use blood sugar to fuel movement. This can lead to a state of relative insulin resistance and if severe, can lead to diabetes, obesity, and metabolic syndrome (high blood pressure, high cholesterol, diabetes).
Goals of Training
Considering these changes that accompany mid-life, it’s important to keep the following goals in mind for athletic performance as well as longevity and vitality.
Hypertrophy. Muscle mass is the foundation upon which muscle strength is built. To be strong, muscle mass is needed. Mass is also important for the metabolism of blood sugar and optimizing the function of insulin.
Strength. The ability to move weight is important for activities of daily living as well as for many competitive sports or high-performance occupations. Yard work, moving boxes or furniture, carrying groceries, and even rising from a chair require muscle strength. This is where hypertrophy and strength diverge. One can be strong without an over-abundance of muscle mass, and an over-abundance of muscle mass does not necessarily correlate with overall strength.
Power. The ability to move a load over time is defined as muscle power. Greater loads over a shorter time yield the greatest power. The nervous system now enters the equation because the ability to react to a stimulus in a coordinated way instantaneously requires a coordinated effort between the skeletal muscles and the nervous system. Some examples include tripping and breaking your fall, evading an obstacle, and team sports such as rugby, Olympic powerlifting, and CrossFit to name a few.
Resistance Training - Getting Started
In general, it is well-accepted that lower load, higher repetitions, and thus a greater duration of time under tension increase local muscular endurance. Conversely, greater loads, lower repetitions, and thus shorter times under tension are more effective for increasing muscular strength. However, in untrained women, lower weights at higher repetitions have been shown to build hypertrophy and strength.
For clients of all ages who are new to weight training, starting with lower weights and focusing on sound mechanics of movement is the goal. Engraining those good habits with higher repetition schemes will familiarize the untrained athlete with safe movement patterns, stimulate hypertrophy and strength, and build confidence upon which to advance their training.
PLUG: As a former Les Mills BodyPump instructor, I experienced firsthand the benefits of a higher repetition/lower weight strategy for introducing weight training to untrained (and trained) individuals in a safe, fun, and friendly group setting. I would highly recommend checking out a class at your local gym or through Les Mills On Demand.
Resistance Training - Building upon Your Foundation
Once you are familiar with and practiced in the basic movements of weight training (squats, deadlifts, bench press, and shoulder press), there are many ways to advance your training to achieve your training goals.
When designing resistance training programs, there are multiple variables that can be adjusted to achieve a given stimulus, depending on training objectives. We can adjust load (or weight), the number of repetitions, the tempo of the repetitions, the range of motion, and work-to-rest ratios. In the CrossFit world, we add another dimension by pairing short endurance activities or other complimentary movements with weightlifting segments to challenge moving load under fatigue.
What is repetition tempo?
Tempo: Refers to the timing of eccentric (muscle lengthening ie “lowering into a squat”) and concentric (muscle shortening ie “rising from the squat”) phases of movement.
Squat: 1/1 = 1 second eccentric (lower) and 1 second concentric (rise) = total 2-second repetition time
Squat with a pause at the bottom: 2/1/1 = 2-second eccentric, pause for 1 second at the bottom and 1 second concentric - total 3-second repetition time.
Training for Hypertrophy - A meta-analysis of studies reviewed by Mang et al in the ACSM Health and Fitness Journal reports a wide range of repetitions (3-35 repetitions) and repetition tempo durations (0.5 - 8 seconds) are effective for building muscle mass. Below are two of my personal favorites, but there are a number of possible variations:
Squats. Every 2:00 (E2:00) on the 2-minute mark, perform 10 repetitions for 5 sets. Tempo: 1/1 at 50-60% of 1 repetition maximum (1RM).
Squats. Every 3:00 on the 3-minute mark, 7 repetitions for 5 sets. Tempo 2/1/1.
Training for Strength - Mang et al also report that the collective literature supports lower repetition ranges and higher load for increasing muscular strength. Below is an example of a program designed by my amazing Coach, Erika Snyder, to help me increase my strength. For strength building with lower repetitions/heavier weights, it is important to allow enough recovery (3-5 minutes) between sets.
Week 1 - E4:00 1 set of 5 repetitions (1/1 tempo) x 3 rounds at 65%/75%/85% of 1RM
Week 2 - E4:00 1 set of 3 repetitions (1/1 tempo) x 3 rounds at 70%/80%/90% 1RM
Week 3 - E4:00 1 set of 5 reptitions (1/1 tempo) at 75% 1RM, 1 set of 3 repetitions at 85% 1RM and 1 set of 1 repetition at 95% 1RM
Week 4 - De-load week: E3-4:00, 1 set of 5 repetitions (1/1 tempo) x 3 rounds at 40%/50%/60% 1RM
Week 5 - Heavy single re-test. Warm Up with 2 sets of 3 repteitions and 2 sets of 2 repetitions (3 minutes between sets) at 50%-75% 1 RM. E4:00, 1 repetition E4:00 x 3 rounds at 85%/95%/100+% 1RM (all at 1/1 tempo).
If you do not know your 1RM, that’s ok! The goal is to complete the repetitions above unbroken with the heaviest load you can do while maintaining safe and solid movement mechanics.
Interestingly, a study by Wescott et al. showed that super-slow tempos (repetitions lasting more than 10 seconds each) have also been shown to be effective for increasing strength. Some examples include 1 set of 8-12 repetitions with a tempo of 4/1/2 was effective. Another study group performed 1 set of 4-6 repetitions with a tempo of 4/10 and reported increases in strength.
Training for Power - Muscular power equates to force x velocity, which is the ability to move heavier weight in a short period of time. Logically, if we think about repetition tempo, shorter time intervals will generate greater power. For the eccentric (lengthening) phase, 1-2 second durations generate greater barbell velocity and power when compared to longer durations. During the concentric (shortening) phase, rapid (<1 second) durations generate the greatest power. However, there is evidence that muscle power can be increased over the long term with 2/2 repetition tempos.
Putting it all together
The end goal of resistance training is to support our muscles and bones for athletic training, sport, high-performing professions, and longevity into our 8th, 9th, and even 10th decades! These activities are complex and require muscle mass, strength, and power and thus our training programs should reflect these goals. Due to the overlap in programming that may effectively train more than one of these elements at a time, a wide variety of movement repetitions, tempos, and loads can be utilized.
Constantly varying these metrics and even adding complementary movements to a resistance program as is done in CrossFit, adds an additional level of nervous system stimulation and thus greater challenges to physical adaptation and greater levels of fitness. Lastly, the culmination of these efforts results is in the activities themselves. We train in the gym for the activities we engage in outside of the gym, and this comprehensive strategy will keep you performing at your best in your sport and in life for years to come.