Expert Insights from Zac Robinson, PhD(C): Strength Training, Nutrition, and Muscle Health

Written and medically reviewed by Rich LaFountain, PhD

as interviewed by Rich LaFountain, PhD

Zac Robinson, PhD(C), is a strength-training researcher, practitioner, and podcaster. He takes a holistic approach to improving strength training for human health and performance — an activity that is just as essential for health and longevity as fasting.

In addition to helping people improve body composition and metabolic health through strength training (see how well these goals align with fasting goals?), his podcast and website translate emerging research in the field of resistance exercise so others can put that science into practice.

Q&A with Zac Robinson: Applying and Translating Research into Effective Strength Training Across Our Lifespan

Q: Can you tell us about your experience as a researcher and a practitioner in the world of strength training?

A: I had great experiences early on while I was an undergraduate, helping and supporting clinical and behavioral exercise research in primarily arthritis and cancer patients. After I graduated from undergrad, I was accepted into a graduate program where my research focus — then and now — included more healthy, trained participants. Data Driven Strength started as me helping a few friends from a coaching perspective. I was not paid, but the experience of helping people become safer, more effective, and more enthusiastic about their strength training sparked my interest in continuing to develop as a practitioner focused on coaching and programming.

It didn’t take long before I discovered great synergy between being both a researcher and a practitioner. Sometimes researchers can be distant from the actual training and coaching world; similarly, not all practitioners in the field of strength training are up to date on research that might enhance their ability to help the patients, clients, or teams they work with. There is a reciprocal relationship between research and working directly with people who want to gain strength and improve health. High-impact research is often driven by real-world experience, and strength training is more effective when research evidence can be translated and applied at an individual level.

Q: How does strength training for longevity differ from strength training for performance?

A: The major difference between strength training for general health and longevity versus competition is that competitive-strength athletes seek to optimize. Competitive-strength athletes have very specific goals for each training session, and they have more sophisticated, periodized training so they can reach their peak performance at the time of their competition. 

For general health and longevity, you need to build and maintain plenty of strong, healthy muscle mass, but you don’t need to invest the same level of time and effort in optimization. Instead, you want to activate and maintain healthy muscle mass so that you can “live strong and prosper” while reducing age-related disease, frailty, and fall risk.

Research solidly suggests that you get most health and longevity benefits from just two or three high-quality strength workouts each week. This is great because most people are busy, so it’s encouraging to know that if you can invest 60–120 minutes a week to train your muscles and bones, you will get results. Not only that, but the results compound over time, which makes your consistency in strength training for longevity well worth the effort.

If you’re interested in fat loss, muscle or lean mass gain, and general health and longevity, I suggest you focus on building a manageable resistance training regimen that fits your schedule and lifestyle. Consistency is the number-one strength-training principle for longevity.

After all, there is no benefit associated with a resistance-training program that is not put into action. You do not have to isolate muscles and slog through 20 sets of various biceps-curl exercises, for example. Instead, focus on truly engaging your mind and body with a couple high-quality sets of exercises that activate all your major muscle groups. If you strength train a few times each week and incorporate basic movements like squats, deadlifts, shoulder presses, bench presses, and pull-ups, you’re going to make tremendous progress in slowing the effects of aging.

Q: How do you help people understand what high-quality sets are and consistently incorporate high-quality sets into their workouts?

A: High-quality sets are sets in which you are stressing your muscles. Muscles that are not stressed (at least a little bit) are not going to respond, grow, and get stronger. A lot of what you are trying to do in the gym is expose your body’s muscles, tendons, skeletal structures, and even mitochondria to something new or challenging. Your goal is to complete exercises that are difficult but not so difficult that your form breaks down, motivation wanes, or, worst of all, you get injured. Injuries certainly violate the primary principle of consistency of strength training for health longevity!

The best methods I know of that are supported by science to maintain high-quality sets in strength training are associated with proximity-to-failure. I co-authored a meta-analysis on proximity-to-failure that was published this year. Proximity-to-failure is a way of understanding and communicating how close you come to being unable to physically perform a lift. Using pull-ups as an example, this would be your estimation of how many more reps you could successfully do before you need help and are not able to perform the pull-up on your own (a.k.a. failure). “Failure” can have a negative connotation, but with strength training, failure is usually the best anchor for you to ensure that you’re consistently achieving high-quality sets during your workout. 

Q: How might someone apply or put proximity-to-failure into action, especially if they are unfamiliar with this type of training?

A: It’s fairly common for people to get a strength-training program online, develop their own, or even hire a trainer or coach to guide them through a workout program. Usually, the programs are based upon a person’s maximal ability to lift a given weight one time. Specific weights or percentages are then organized and structured into workouts so people have a clear plan heading into the gym. Having a plan is wonderful — it’s much better that you know ahead of time what lifts and exercises you’re going to do. However, the rigid percentages or weights can sometimes pose a problem since your energy levels, stress, readiness to train, and therefore ability all vary from day to day.

Proximity-to-failure training allows you to set the intensity of your workout to fit your overall abilities on any given day. Certain tools, validated in strength-training research, can help you train this way to keep your workouts safe and effective. Rating of perceived exertion (RPE) is one such tool. RPE is a scale, usually 1–10, with 10 being the maximum effort you can put forth. High-quality sets usually reside in the 7–10 range, but the weight itself may shift. Rather than simply providing a directive like “do four sets of six reps of a 150-pound deadlift,” you would do four sets of six reps at a weight that corresponds to an RPE of 8. That might be 150 pounds on an average day, but on a day you feel outstanding, that weight might be more like 175 pounds. This is an advantage of RPE — it would be a shame to limit yourself if you can do more at the same perceived level of exertion! On the flip side, proximity-to-failure training can also help you to pull back when you’re already tired or training is abnormally challenging. 

Another common method we use is repetitions in reserve (RIR). This method means you meter your weight based upon how many additional repetitions you could still do after you stop the exercise. For example, let’s say you can bench press 120 pounds ten times, but no more than that. On a day when the workout plan is to do three sets of bench press at an RIR of 1 or 2, you would then stop at seven or eight reps, knowing that you could probably get those additional repetitions if you pushed all the way to failure. Again, this method enables you to engage in autoregulation, or to modify your workout so that you are challenged but not overstressed.

Q:  Based upon your experience working with the entire spectrum, from clinical populations to competitive-strength athletes, is there anything that you believe applies universally to anybody interested in resistance training?

A: Autoregulation is the training variable that’s probably the most widely applicable across all goals, interests, and experience levels. Autoregulation encourages manipulation of workout sessions to fit the context of your life and stress levels on any given day. 

For most people, optimizing their strength exercise is not the most important thing they do each day. External demands, stress, fatigue, or even aches and pains can impact a person’s motivation or ability to exercise. Autoregulation allows you to factor your overall readiness to perform resistance exercise into your workout. Some days, things will feel great, and maybe you can lift more than expected; you should try to push a little bit on those days. However, on a day that you are not feeling your best, rather than cancel the workout or “muscle through” and increase your potential for injury, you are usually better off adjusting your exercise plan on the fly. 

Autoregulation goes hand in hand with the flexible training methodologies we previously discussed, like RPE and RIR. Usually, you can get a feel for your readiness during the warm-up. If you notice that your body feels stiffer or creakier than normal, or the weights feel slightly heavier, you can adjust things right then and there. You can determine the new target weight using RPE or RIR: If you planned to perform ten repetitions of squats at 100 pounds, maybe back off 100 pounds and shoot for 85 or 90 pounds instead.

Autoregulation is not limited to strength training; you can also use it in other forms of exercise. For example, you could just as easily scale your distance or duration in a running workout. Over time, you can develop an intuitive barometer of your stress levels, which can pay dividends even outside of exercise. Perhaps you notice, while you’re exercising, that you’re feeling flat. You can certainly adjust your workout plan, but you may also opt to lean into more relaxation or leisurely, stress-reduction activities. Overall, autoregulation will help you be consistent in the long term and to protect you from things like burnout or injury. 

Wrap-Up: 5 Key Strength Training Tips from Zac

Strength training is for everyone, whether you’re a competitive athlete or just trying to improve your health and longevity. Here’s a summary of his top takeaways:

  1. Consistency in strength training pays huge dividends in health and longevity, so find a plan that you’ll actually stick to, and start building the habit!
  2. Key strength exercises include squat, deadlift, shoulder press, bench press, and pull-up.
  3. Work your way up to strength training two to three times per week for a total of 60–120 minutes.
  4. Use proximity-to-failure tools to challenge yourself for a high-quality strength workout. RPE of 7–9 out of 10 or RIR of 0–2 are great targets.
  5. Always consider your readiness to train so that you are safe and efficient with each strength-training session. (And factor that feeling into how you go about the rest of your day!)

For more practical wisdom and education about living a healthy lifestyle, please visit Zac’s website, follow him on social media, and subscribe to Data Driven Strength Podcast and his YouTube channel.

Rich LaFountain, PhD
Posted in Health & Science

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