“Who will you be when you no longer bow into the shape of other people’s desires?”
Danielle Friedman, author of “Let’s Get Physical”
It was many years ago, while teaching a Senior Strength class, that I came to appreciate the impact strength training can have not only on the body, but on a person’s confidence, feelings of safety, and even self-worth. Senior Strength was a weight training class taught to residents of an independent living community. The average age was 78, with one participant as old as 95 and others in their mid-sixties. Given that the group was born before World War II, their attitudes about fitness and exercise were very different from my own. Most people attended reluctantly, coming primarily on the recommendation of a physician or from prodding by adult children. Plenty came only to socialize or as something to do before lunch.
It was a hard group to keep on task. They did the minimal amount necessary, using the lightest weights possible while moving erratically, frequently stopping, getting up from their chairs and moving around, sometimes leaving the room. Typically, one or two fell asleep. They were easily distracted—singing to the music, complaining about the music, sharing stories, telling jokes, scolding people for talking. I felt more like a social director than an instructor. There were exceptions, however, including three women who came faithfully each week. They were quiet and focused, carefully listening to my cues and following my instructions. After class they would ask questions about their form as well as guidance about using heavier weights.
I taught this class for over seven years, but what I remember most is how the class changed these three women. Every so often one would share a success story—carrying a full laundry basket down two flights of stairs without a struggle, lifting a suitcase and sliding it into an overhead compartment, carrying a sleeping three-year-old granddaughter to the car. None of them developed “Michele Obama” arms, nor did they graduate to the weight room or move anything heavier than 15 lbs. Their successes were personal and subtle, with stories that reflected moments of regained independence and restored confidence. Lifting weights helped them feel safe and secure in their bodies, which for them was a novel experience. As one woman shared, “I am no longer fading away. Having strong muscles makes me feel relevant again. I will not be ignored.”
Increasingly, research is supporting the experiences of these three participants, showing that weight training doesn’t just create strong muscles, it also works the nervous system in ways that help promote a sense of safety and calm. Studies show that lifting weights fosters a stronger connection to one’s body as well as to the earth, a physical and subjective sensation that is sometimes referred to as “grounded-ness”. The simple act of holding a heavy weight or pushing the body against resistance recruits the proprioceptive and vestibular systems that help us establish a sense of where our body is in space. It also engages interoceptive awareness in which the brain integrates information from various regions of the body, which enhances self-awareness. The nervous system also benefits: unlike cardio exercise in which effort is maintained at an elevated level over an extended period of time, the work of moving a heavy load comes in increments, characterized by a burst of work followed by a rest period. These breaks give the nervous system a chance to settle down and reset, which expands our tolerance for work while avoiding feelings of being overwhelmed.
Weightlifting has come a long way from the stark, dank rooms of the past, many of which were stacked with enormous free-weights, kettlebells, and other strange looking equipment. These were places steeped in toxic masculinity, filled with bulging, grunting bodybuilders straining against the weight of barbells loaded with heavy plates. Weight training has since evolved into a form of exercise that is welcoming to a much wider audience. And the fusion of weight training with high intensity resistance activities such as boxing, box jumps, and pull ups has drawn greater numbers of both men and women to work with weights than ever before. In the mid 2000’s, research showed that, in most gyms, the ratio of men to women in a weight room was 27 to 1, while 75% of its cardio equipment was occupied by women. With the introduction of programs such as CrossFit, bootcamps, and group training classes such as Les Mills’ Body Pump, weight rooms now have a greater diversity of people and lifting weights is no longer the sole territory of grunting bodybuilders.
But not all strength training programs are created equal. There can be a great deal of confusion in what types of training build strength versus power, speed, or endurance. There is a basic physiology to lifting weights that is dampened when we mix it up too much with other forms of exercise. Muscles work in a very specific way; the strength gains from lifting weights follow a precise formula that can be altered only within a small margin of error. Stray too far from the formula and you will likely wind up with fewer strength gains and, unfortunately, more injuries.
Muscle physiology is a dense topic, a combination of chemistry, biomechanics, and physics. But we need not get lost in the weeds of the science of muscle tissue to gain an appreciation of how to build strength. Let’s skip the wonky details and focus instead on the relationship between muscle fibers and moving weights. What needs to happen in the muscle to make us stronger?
Skeletal muscle is made up of two different kinds of fibers, slow twitch and fast twitch. The type of fiber—slow or fast—that is recruited depends on the task they are required to perform. Slow twitch fibers are recruited primarily during low intensity endurance activities, as well as most of our daily activities, when the requirement for generating force is low. These fibers use oxygen as their source of energy and are responsible for the endurance of a muscle. Lifting a light weight numerous times without much difficulty engages mostly slow twitch fibers, which will not necessarily make a muscle stronger, but it will make it more resistant to fatigue. Whereas there is only one type of slow twitch fiber, skeletal muscle contains a variety of fast twitch fibers, each performing a specific type of task. Type IIa fast twitch fibers generate more force and do so more quickly than slow twitch but because they do not use oxygen for their energy source, will fatigue easily. These are the fibers used for shorter, higher intensity movements that require a burst of force, much like what happens when you attempt to move a heavy weight. The more force required to move the weight, the more recruitment of fast twitch fibers. There is another type of fast twitch, IIx, which is not easily activated by the nervous system. These fibers provide a fast contraction, creating the type of power seen in explosive events, such as an all-out sprint, jumping, or throwing.
Skeletal muscle responds to the forces that are applied to it. Responding first by engaging slow twitch fibers, it switches to fast twitch, IIa, when it encounters increasing resistance. In the absence of a heavy load, slow twitch fibers dominate and strength gains are minimal. Herein lies the precision that is necessary to become stronger. We must expose the muscles to the right level of resistance—not so much that the muscle is overwhelmed but enough to recruit fast twitch fibers. So, although bootcamps and group strength classes may be fun and challenging, to build strength we need to follow the formula of consistently exposing the muscles to an increasing load. That is the work of building muscle and getting stronger.
At some point in weight training, we may encounter a significant obstacle that impedes progress, one that is not a property of muscle but is generated by the mind--our desire to run away from discomfort. Pick up a heavy weight, one that is challenging, and what is your first reaction? Most likely it is not joy or giddy excitement. Heavy resistance is typically met with a corresponding level of unpleasant sensations. We hold our breath, grit our teeth, we may even let out a grunt. Provided the weight is not beyond our physical capacity, we may be able to muster enough force to overcome the resistance. But if our habitual response to unpleasant sensations is to run away, we most likely will give up quickly, sometimes without even trying. Some of this avoidance is a natural part of the learning curve associated with weight training. The initial six to eight sessions of weight training is mostly neurological, stimulating the nervous system and recruiting motor units, so lighter resistance helps to avoid injury. But eventually we must encounter heavier loads to get stronger. It is at this point when our reluctance, not neural responses or motor units, will determine how much weight we will lift. The strength of a muscle goes beyond the muscle’s physical capacity. We also need the tenacity and willingness to push back against resistance.
Luckily weight training is a methodical process, one that involves gradual exposure to increasing load. We aren’t required to make a sudden leap from light resistance to a heavy load; that is, in fact, counterintuitive and a recipe for injury. Strength gains are slow, subtle, and unfold gradually. By maintaining an awareness of how we face unpleasant sensations, we can learn to adjust how we respond to forces that oppose us. The process of strengthening our muscles requires us to sustain contact with resistance and respond by generating the desire to push back. With repeated exposure to short bursts of discomfort, perhaps clenching our teeth and even letting out a grunt, we begin to change our relationship with our body.
Whereas cardio builds our physical and mental capacity for adaptability and resilience, moving heavy weights plants us firmly on terra firma. It demands we face the forces that put pressure on us and, in doing so, overcome our desire to flee from unpleasant experiences. Each time we lift a heavy weight, we find an opportunity to face our demons. This is one reason weight training is used as a therapy to treat PTSD, anxiety, and depression. And it spurred the transformation in those three women who showed up for class, changing them from feeling like frail and irrelevant individuals to women who “will not be ignored.” So, pick up a weight, face your discomfort, and push back. Who will you be when you stand your ground, grow your confidence, and find safety in the physical body you call home?
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