Science Spotlight: Israel Halperin

Interview by
Adam Tzur (Sci-Fit on FB)

Published: March 19, 2019

Israel Halperin sci-fit


Learn to work from a place of not knowing what the best solutions are to your coaching problems.

Table of Contents


Profile of Israel Halperin

Israel Halperin YCC 2019 Sci-Fit

Photograph: Israel lecturing during the Youth Coaching Conference in Singapore


Israel Halperin is a scientist that researches multiple fields such as:

  • Coaching strategies
  • Combat sports
  • Metascience and methodology (how to do proper research, and how to improve science)
  • Muscle fatigue
  • Others (e.g. mind-muscle connection)

What you can do:

Israel has previously edited, reviewed, and contributed to Sci-Fit’s articles about cluster sets and drop sets and one of our keto articles.

Israel Halperin Coaching Josh Sci-fit

Photograph: Israel coaching world champion kickboxer, Josh Tonna.

Israel’s Insights

In this section, Israel shares insights he has discovered through his research, experience, and coaching.

What are your top three practical tips for coaches?

  1. Embrace uncertainty. Learn to work from a place of not knowing what the best solutions are to coaching related problems and to feel comfortable with it. It is perfectly acceptable to say “good question, I am not sure what the answer is”.
  2. Involve your clients in the decision making process. Encourage them to voice their opinions and share their insights. They are likely your best source of information.
  3. Avoid taking sides in false dichotomies and learn to spot them immediately. False dichotomies are very common in the coaching sphere, and in many ways are quite attractive (e.g., resistance training vs. aerobic training; personal experience vs. research; free weights vs. machines), but they are rarely helpful or accurate. Few things boil down to either/or. Especially when dealing with humans. Embrace the “it depends” approach.

Israel recently held a talk about coaching strategies and critical thinking:

What are your top three tips for combat athletes such as MMA fighters?

  1. Combat sports relies heavily on making accurate decisions and predictions about what the opponent is going to do next. Reading your opponent so to speak. To fine tune this decision making ability, you must dedicate a whole lot of time practicing activities that require you to… make decisions. This means sparring, play sparring, unanticipated pad work, and other drills that force you to quickly, and hopefully accurately, respond to the actions of your opponent.
  2. While strength and conditioning sessions are a crucial aspect of combat preparation, I regularly encounter athletes who seem to overemphasize strength and conditioning over technical, tactical and sport specific training. Don’t lose sights of your goal. If you want to become a better fighter, dedicate most of your time to practicing your sport, not chasing numbers in the weight room.
  3. Don’t forget to have fun. Fighting is hard. On the body and on the mind. If you are constantly feeling worn out, down, and finding yourself training because you feel like you have to, consider taking some time of, switching gyms, or at the very least, think about what you can do to improve the situation.

What are your recommendations for researchers?

  1. Surround yourself with people you enjoying collaborating with. It takes time to find them but it is well worth the effort. Over the years I found a few colleagues that I work well with and my productivity sky rocketed. Note that they don’t have to be geographically in the same country or city. Most of my collaborators don’t live in Israel.
  2. Continuously work on improving your statistics. It is an endless journey and can be quite frustrating at times, but it is critical to stick with it. Especially nowadays when methods and statistical analysis are (rightly so) in the spotlight.
  3. Read outside your field. Some of my most important aha moments came when I read books and articles from psychology, medicine and philosophy. These aha moments also feed into my research agenda and allow to me ask cool interdisciplinary questions.

Israel Halperin YCC sci-fit

Photograph: Israel lecturing in Youth Coaching Conference in Singapore


Hello, Israel! Could you give our readers a short introduction about what you do in the world of fitness and nutrition?

Hello Adam, thanks for having me!

What I do in the world of fitness seems to change over time. For many years I worked as a strength and conditioning and kickboxing coach. Nowadays the majority of my time is dedicated to sport and exercise research. I still make an effort to coach, as first and foremost, I love coaching. But also because it keeps me connected to the trenches and provides excellent research ideas and opportunities.

I also enjoy teaching, and until recently I taught a course entitled evidence based practice in fitness and rehabilitation. The course was designated for working professionals and dealt with decision making processes and how to critically appraise research. Now as a full time academic, I will soon begin supervising MSc and PhD students, as well as teaching courses within the University.

Israel Halperin Pads sci-fit

Photograph: Israel holding pads for kickboxing world champion, Josh Tonna

Could you tell us about the research and teaching you do at Tel Aviv University?

I started working in Tel Aviv University this January, and while I am busier than ever before, I love every minute of it. I have a joint position in the School of Public health in the Sackler faculty of Medicine, as well as the newly established Sylvan Adams Sport Institute. My research focus and interests are very well aligned with the with those of the Sylvan Adams Sports Institute: conduct applied research with the goal of improving human performance. Teaching wise, I am planned to teach two courses that I am currently developing in the soon-to-be-approved Masters in exercise physiology. The first will revolve around training methodology of elite athletes and the second around advanced topics in resistance training.

What are your main scientific fields of interest?

I have a number of research avenues I am currently pursuing:

The first avenue is to investigate how to optimize coaching strategies to enhance motor learning (e.g., teaching how to squat), performance (e.g., squatting heavier loads), motivation and training adherence.

Examples of Israel’s coaching strategies

In our training sessions, we can choose to provide our clients with choices. For instance, should we allow clients to choose:

  • Which exercise to begin with?
  • How long they should rest for?
  • When to receive verbal and/or visual feedback from us?

A growing body of evidence indicates that the answers to these questions are positive. That is, we should allow our clients to make certain decision concerning different aspects of the training sessions. By doing so we will enhance their learning, performance, and motivational levels.

The second avenue is to investigate how people perceive their level of effort, pain, and fatigue before, during, and after they exercise. 1These are called subjective scales. We commonly measure this using scales that range from 0 to 10 with 0 being no effort/fatigue/pain and 10 being the maximal levels of effort/fatigue and pain people can tolerate.

There are many different scales out there being used for monitoring and prescription purposes. For example, we can ask our client to end the set when he or she reaches 8 out of 10 on the effort scale. Alternatively, if we regularly monitor our client’s fatigue levels, we may notice that prior to beginning a given session the scores are unusually high and may thus decide to scale down the intensity of the planned session. Within this research theme, I would like to figure out if some scales are better suited than others to monitor specific outcomes such as over training, injuries, drop-out rates, and performance. I love this field of research as it is has practical potential and requires an interdisciplinary perspective.

Finally, I plan to continue investigating ways to improve how science is done in the exercise and sport disciplines as well as develop ways to better communicate scientific outputs to applied practitioners. Study ways to bridge to gap, so to speak.

Where did your interest in kickboxing originate? Do you aim to publish more research on combat sports?

Where my passion for martial arts/combat sports originated remains a mystery. I am the only person in my family who practices martial arts. I have vivid memories of myself as a young boy sneaking down stairs to the living room to watch American ninja films. While I am obviously not competing or even seriously training anymore, I still hit the bag at least twice a week and occasionally have an athlete or coach I work with hold pads for me. I forbid myself to spar these days as I painfully learned that blows to the head don’t go hand in hand with my attempts to run statistical analysis. I am also up to date with the kickboxing scene and most certainly plan to conduct combat related research in the future. Israel (the country…) produces excellent combat athletes, most of which I work with one way or the other, so once my lab is ready to go, combat research is on my to-do list.

Should we lift weights in front of mirrors?

That depends on your goals.

My tentative suggestion would be to exercise in front of mirrors if your goals are more aesthetically driven and if you enjoy it. I would caution against training in front of mirrors when performing heavy, complex exercises such as squats and deadlifts and when ones goals include maximal strength development and technique enhancements. While training in front of mirrors may offer some benefit, they could lead one to mostly rely on vision as the sole source of information concerning technique refinement, and mostly from one main angle. This could lead people to disregard and under-develop their ability to extract useful information from other senses.

In a study conducted in 2016 we found that both maximal jump height and a static bicep curl were unaffected by the mirror compared to the no-mirror control condition. However, more research is most definitely needed before we can establish how mirrors affect performance. There is just not enough literature on this topic at the moment.

What are your thoughts on the usefulness of Electromyography (EMG)?

This is a good question. In 2017 I co-authored a review paper led by Andrew Vigotsky and a brilliant team of scientists on EMG in exercise science.EMG is a great tool that can assist us learn a lot about the motor system. The problem is when EMG is viewed, treated, and interpreted, in an overly simplistic manner. My advice for the readers is the following: fight the temptation to draw strong conclusions based on EMG studies. As attractive as some of their conclusions may be (e.g., higher EMG amplitudes = greater strength or hypertrophy adaptations) the reality is that things are more complex than that.

Israel Halperin EMG

Photograph: Israel’s biceps is hooked up with EMG electrodes for an isometric strength test

You’re passionate about metascience (“the science of science”) – how do you want to improve research?

Very much so. For one, now that I have a full time academic position, it will be easier for me to practice what I preach. This means pre-registering my studies, and in the near future, also begin using registered reports (e.g., submit my methods for review rather than the complete study). I also hope to conduct multi center studies with other labs around the world in hopes of overcoming the small sizes associated with our field.

It is very challenging to recruit adequate samples for research purposes and one possible solution is to run the same study in parallel in a number of labs around the world. I also plan to dedicate some of my research efforts to direct replications. We need them badly in our field. These are my key plans. Now that there are here in the open, there is even a greater pressure on me to succeed 🙂

Israel’s Research and Articles

Peer-reviewed journal publications

Publication Link Year Type
Coaching cues in amateur boxing: An analysis of ringside feedback provided between rounds of competition Link 2016 Observational study
Choices enhance punching performance of competitive kickboxers Link 2016 RCT
The effects of attentional focus instructions on punching velocity and impact forces among trained combat athletes Link 2016 RCT
Physiological profile of a professional boxer preparing for Title Bout: A case study Link 2016 Case study
Reliability And Validity Of The Single Leg, 3-hop Test In Australian Judoka Link 2015 Correlational study