Lifting weights in a weight room or home gym is a great way to improve multiple facets of physical and mental health. A wonderful aspect of strength training is the ability of the trainer to modify the variables of the training plan in order to achieve different goals. One of the main distinctions that many lifters choose between when starting a weight training program is training for strength, which can be defined as the production of force against an external resistance,¹ or training for increases in muscle size, which is also referred to as hypertrophy.

How the Body Adapts to Resistance Training for Strength Versus Training for Muscle Growth

While there is overlap in the physiological adaptations that take place in response to strength training versus hypertrophy training, focused training for each of these goals yield slightly different changes in the human body. The main physiological adaptations that yield greater strength in the human body are, interestingly, not an increase in the size of muscles. In fact, muscles can become significantly stronger without growing in size if they are trained specifically for an increase in strength.² 

Increases in strength can be, in large part, attributed to neurological adaptations in the lifter independent of the size of the muscle, especially when a lifter first begins strength training. These neural adaptations to strength training can be defined as changes within the nervous system that allow a trainee to more fully activate large muscles in specific movements and to better activate all muscles required to perform a certain movement, thereby exerting a greater force in the intended direction of movement and thus increasing their strength.³

When combined with adequate nutrition, weight training specifically for hypertrophy leads to increased muscle protein synthesis, a process in which amino acids found in the protein that we eat are incorporated into our skeletal muscle, leading to an increase in the diameter of our muscle fibers and a subsequent increase in the overall size of these muscles.⁴ 

Why Train for Strength?

Weight training with the goal of lifting more weight than you previously could is an effective way to reap the health benefits of resistance training while tracking a metric of success other than a visibly larger muscle. Many people look at famous bodybuilders and celebrity fitness coaches and believe that the main goal for weightlifting is the sculpting of aesthetically impressive muscles. While that can be a worthy pursuit for those who are interested in achieving a visually fit physique, the health benefits of weightlifting are so vast that it would behoove most people to do some type of resistance training without aesthetics as a main focus, and increasing the amount of weight lifted over time can help lifters observe their progress and stay motivated.  

Additionally, strength training has been described as the #1 tool to combat neuromuscular aging. One of the best reasons to weight train specifically for strength is to maintain strength and power as we age. While muscle mass, or the physical size of the muscle, decreases by approximately 3 to 8 percent each decade after the age of 30,^5,6 neuromuscular strength has been found to decline by a whopping 10 percent per year after the age of 50.⁷ Additionally, aging brings about the loss of motor units, which are the pathways of our nervous system responsible for communicating motor function to our musculoskeletal system.⁸ These effects combine in the aging body to impair the ability for movement, yielding muscles that are weaker, slower, less powerful, less steady, and more fatigable. Weightlifting specifically for the maintenance of strength can ameliorate some of this age-related loss of strength, and as a result, keep us moving around unassisted as we enter advanced age.

Training principles for strength versus hypertrophy

A workout plan focused on strength versus one focused on hypertrophy will vary in terms of several variables, including the number of repetitions performed in a set and the amount of weight lifted (also referred to as “intensity”). A strength-focused plan will consist of lifting heavier weights for less repetitions, normally within the 1- to 6-rep range, while workouts for hypertrophy favor more moderate weights for rep ranges of 6 to 12.⁹ Here, “heavier” weights would be defined as a weight that is 80 to 100 percent of the maximum weight that can be lifted for one repetition; for example, someone who can squat a maximum of 100 pounds for one repetition would perform a set of five repetitions at 80 pounds (80% of their one-rep maximum) when training for strength. For hypertrophy, the lifter can stick with roughly 60 to 80 percent of their one-rep maximum during a set. Therefore, that same lifter could squat 60 pounds for 10 repetitions.¹⁰

A note on nutrition and recovery.Nutrition and recovery are important aspects of any weight training plan, regardless of whether your goal is to build muscle or gain strength. Aim to consume 0.64 grams to 0.82 grams of protein per pound of bodyweight per day,¹¹ eat a balanced diet rich in micronutrients and fiber, minimize or avoid alcohol consumption, and ensure you’re sleeping 7 to 9 hours of sleep each night.  

Bigger AND Stronger: Can we do both?

For most casual lifters, weightlifting can yield increases in both strength and muscle size by alternating between the two styles of training with regard to repetition ranges and intensity. This can consist of alternating between periods of strength-focused weightlifting and hypertrophy-focused weightlifting over time. For example, a weightlifter could follow strength-focused weightlifting principles for 12 weeks, then switch to hypertrophy-focused principles for the next 12 weeks. Alternatively, a lifter can alternate between a strength focus and hypertrophy focus on different days of the week, or incorporate both styles of training in one workout, beginning with heavy strength-focused lifts first and moving on to hypertrophy-focused movements after. For advanced lifters and those looking to participate in competitive weightlifting, powerlifting, or bodybuilding, it is generally regarded as inefficient to attempt to train for both strength and hypertrophy concurrently, as the differences in these workout plans will make it difficult to work towards both goals optimally. 

Sources

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