Sure, strength training can make you bigger, stronger, and faster, but did you know that there are a lot of benefits “under the hood” that aren’t quite as obvious? In the previous parts of this series, we explored how getting in the weight room consistently improves cognition and age-proofs your joints and supporting structures. Now let’s take a closer look at how it can also elevate your mood, increase production of certain hormones, and more.
Achieving Emotional Regulation
If you were to list the things that helped you stay on an even keel emotionally, lifting weights might not be on the list. But it probably should be according to a growing body of scientific evidence. While we’ll get into some of the benefits of weight training for men in the next section, these are not an exclusively male privilege. "If women find that resistance training appeals to them, there is some pretty strong evidence coming from a meta-analysis of almost three dozen randomized trials showing that this is something that can benefit their mood," said Dr. Olivia Okereke, an associate professor of psychiatry at Harvard Medical School.[1]
There’s plenty of evidence to back up this statement. For example, a review published in JAMA Psychiatry examined the results of 33 trials and found that regular training reduces depression, anxiety, and worry, while increasing feelings of contentment and satisfaction.[2] This is probably because exercise stimulates production of neurotransmitters like serotonin, acetylcholine, and dopamine. Scientists from the University of Poitiers in France found that committing to a long-term exercise routine also helps people self-regulate their behavior and exert “effortful control” of their habits.[3] Doing so then feeds back into your ability to stick to your workout plan – creating what the authors called a “virtuous circle” between your body and mind. They also noted that physical activity increases willpower and concentration.
Boosting Hormone Release
Over the past few years, there have been more prescriptions issued to men for testosterone than ever before. Some people genuinely need it, but for others, the “low T” diagnosis is a bit blurry because the acceptable range for this growth hormone is very broad. Rather than making an appointment with your doctor, you’d do well to first try strength training several times a week.
A study conducted at the University of North Texas found that while testosterone declines by one and three percent a year in middle-aged men, a resistance training program with sufficient intensity and volume prompts your body to release more of it. This anabolic (i.e. growth-promoting) hormone doesn’t exist for its own sake, but the authors noted, “is considered the major promoter of muscle growth and subsequent increase in muscle strength in response to resistance training.”[4]
Resistance training doesn’t just release anabolic hormones that increase body mass and prompt muscle growth. According to research conducted at the University of Iowa, it also prompts the secretion of chemicals like BDNF (brain-derived neurotrophic factor) that spur your brain to grow new cells (aka neurogenesis) and prompt connections between existing ones. Contrary to the outdated notion of football linemen and other power athletes being big, lumbering dullards, strength work actually makes you smarter.[5]
Improving Cognitive Output
If you consider strength training to be a purely physical activity, think again. It also lights up your mind like a Christmas tree. A European Review of Aging and Physical Activity meta-analysis of 18 previous studies concluded that “resistance exercises and resistance training evoked substantial functional brain changes, especially in the frontal lobe, which were accompanied by improvements in executive functions.”[6] A study published in Sports Medicine did a deeper dive into what exactly such functions are and found that a single strength training session made participants more cognitively flexible (i.e. able to switch between concepts or think about multiple things simultaneously), increased their attention, and enhanced their working memory.[7]
The latter benefit is likely due to the impact that resistance training has on the hippocampus. This region of the brain is responsible for learning, retaining, and recalling information. A study of 120 adults by psychologists from the University of Pittsburgh found that exercise prompted up to 2 percent growth of their hippocampus.[8] While this might not seem like much, it was enough to boost participants’ spatial memory. Another paper published in the Journal of Science and Medicine in Sport compared the cognitive impact of aerobic and resistance training and concluded that both groups improved their task switching ability, which they attribute to exercise stimulating neuro-electric connections in the brain (think of one of those satellite images that shows a brightly-lit city from space).[9]
All the studies referenced above that examined single bouts of exercise found that between 15 and 30 minutes was enough to make meaningful and positive changes. Those that evaluated longer-term interventions suggested that two or three sessions per week could prompt beneficial adaptations in hormone levels, mood, and cognition. So whether you’re looking to increase your willpower, better regulate your emotions, or improve your memory, you might want to start and stick with a well-rounded resistance training program.
Catch Up on This Series
Did you miss the previous installments in this series? Click on the links below to get caught up.
How Resistance Training Age-Proofs Your Body
The Cognitive Benefits of Resistance Training
And check back soon for the fourth and final part, in which we’ll share some unexpected physical benefits of strength training.
1. “Strengthen Your Mood with Weight Training,” Harvard Women’s Health Watch, October 2018, available online at https://www.health.harvard.edu/mind-and-mood/strengthen-your-mood-with-weight-training.
2. Brett R Gordon, Cillian P McDowell, and Mats Hallgren, “Association of Efficacy of Resistance Exercise Training With Depressive Symptoms,” JAMA Psychiatry, June 2018, available online at https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2680311.
3. Michel Audiffren and Nathalie André, “The Exercise-Cognition Relationship: A Virtuous Circle,” Journal of Sport and Health Science, July 2019, available online at https://www.sciencedirect.com/science/article/pii/S2095254619300298?via%3Dihub.
4. Jakob L Vingren et al, “Testosterone Physiology in Resistance Exercise and Training: The Up-Stream Regulatory Elements,” Sports Medicine, December 2010, available online at https://pubmed.ncbi.nlm.nih.gov/21058750/.
5. Michelle W Voss et al, “Bridging Animal and Human Models of Exercise-Induced Brain Plasticity,” Trends in Cognitive Sciences, October 2013, available online at https://pubmed.ncbi.nlm.nih.gov/24029446/.
6. Fabian Herold et al, “Functional and/or Structural Brain Changes in Response to Resistance Exercises and Resistance Training Lead to Cognitive Improvements – A Systematic Review,” European Review of Aging and Physical Activity, July 10, 2019, available online at https://eurapa.biomedcentral.com/articles/10.1186/s11556-019-0217-2.
7. Jan Wilke et al, “Acute Effects of Resistance Exercise on Cognitive Function in Healthy Adults: A Systematic Review with Multilevel Meta-Analysis,” Sports Medicine, March 6, 2019, available online at https://link.springer.com/article/10.1007/s40279-019-01085-x.
8. Kirk I Erickson et al, “Exercise Training Increases Size of Hippocampus and Improves Memory,” Proceedings of the National Academy of Sciences, January 31, 2011, available online at https://pubmed.ncbi.nlm.nih.gov/21282661/.
9. Chih-Han Wu et al, “Effects of Acute Aerobic and Resistance Exercise on Executive Function: An ERP Study,” Journal of Science and Medicine in Sport, December 2019, available online at https://www.sciencedirect.com/science/article/pii/S1440244019304177.
Tim DiFrancesco, PT, DPT spent 6 seasons as the Head Strength & Conditioning Coach of the Los Angeles Lakers and is the founder of TD Athletes Edge. He is nationally renowned for his evidence-based and scientific approach to fitness, training, nutrition, and recovery for athletes and fitness enthusiasts.