Tag: strength

How Long To Rest Between Sets?

How long to rest between sets?  It’s a question every new lifter asks, and an issue that experienced lifters are constantly trying to manipulate to maximize their results.  If you walk into a gym that houses serious strength athletes you might see them take 5-10 minutes between their peak training sets.  Once you start doing the math and realize how long you will be in the gym if you are taking five or more minutes between sets it creates a long enough workout that it becomes demotivating.  Most people just don’t have two hours to spend on their daily workout.

In the average commercial gym where most people are concerned with how they look in addition to getting stronger we see rest times that vary from less than a minutes to a few minutes.  Often the driving factor is if someone is working out alone or socializing with others.

There is a general gym belief that when you are training for hypertrophy (increased muscle size) then rest periods of around a minute are optimal.  If you are training for peak strength development then approximately 3 minutes tends to be the most common advice.  Those trying to maximize calorie burn are keeping their rest periods to below a minute.

So what is the right answer?  Should you be jumping right to your next set or sitting back and watching the minutes go by?  In a 2016 study Schoenfeld et al. attempted to help answer this question by looking at changes in strength and size when subjects used either a 1 minute or a 3 minute rest period.  Test subjects were broken into two groups and with the exception of their rest period did the exact same workout, 3 times a week for 8 weeks.  Each workout consisted of 7 exercises, each done for 3 sets of 8-12 repetitions.  The subjects were tested for maximum strength with their 1 repetition maximum for the bench press and back squat.  Muscle endurance was tested with a bench press done at 50% of the 1RM done to failure.  Muscle growth was measured utilizing ultrasound at the elbow flexors (biceps and brachialis), triceps and quadriceps.

All of the subjects were injury and drug free men ages 18-35 with at least 6 months experience lifting weights.  This ensured that any gains were not the result of early neurologic adaptations to beginning a training program.  The subjects were pair matched to ensure that there were similar subjects in each experimental group.

The training programs consisted of barbell back squats, plate loaded leg press, leg extension, flat barbell bench press, seated barbell military press, wide grip pulldowns and seated cable rows.  During each set of 8-12 repetitions the subjects trained to momentary muscular failure and the weight was adjusted between sets to keep the subjects achieving failure in the designated repetition range.  There was an attempt to consistently raise the weight as subjects were able to.  This selection of exercises and approach towards managing loads is very similar to what is commonly seen in many fitness settings.

The Results

There was clearly a winner when it came to strength improvements.  In the back squat both the long rest period (3 min) subjects and the short rest period (1 min) subjects saw statistically significant improvements, however the long group had a 15.2% improvement and the short group had a 7.6% change.  For the bench press the long group increased 12.7% while the short group only improved 4.1%.

When it came to the the 50% bench press test for muscular endurance both groups saw significant improvements though we again see the long group outpacing the short group with a 23.2% change as opposed to a 13% improvement.

While the existing common recommendations for muscle growth are around the 1 minute period, the results of this study suggest just the opposite.  For the elbow flexors the long group had a 5.4% improvement and the short group had a 2.8% change.  When it came to the triceps the difference between groups was even more notable.  The long group improved by 7% while the short group only saw changes of 0.5%.  In the anterior quadriceps the pattern continued with the long group seeing a 13.3% change while the short group had a 6.9% improvement.  For the vastus lateralis the long group changed 11.5% and the short group 10%.

While it was expected that we would see strength improvements that clearly favored the longer rest periods it was surprising to see that muscle growth also favored the longer rest.

One notable aspect of the research design that has also popped up in other studies is that the subjects performed their exercises to momentary muscular failure on all of their working sets.  There seems to be a trend within the research that when sets are taken to failure, more significant outcomes are seen.  Now don’t go rushing back to the gym and swear that every set needs to be done this way.  This isn’t a topic that has been closely studied, it is just an observation that some researchers and I have made.  In studies where the volume of work is more closely controlled to match up different experimental groups it often means certain subjects are not training to failure and when those studies are compared to ones where subjects are training to failure often differences are seen.

This dovetails with the question of training volumes.  In this study the subjects in the longer rest group recovered more and as a result were able to lift with more total volume then the shorter rest subjects.  To what extent this extra volume that the longer group was able to lift drove their greater levels of improvement is an important question to ask.  Other studies have also raised similar questions, if variables such as training to failure or more sets which produced more volume lifted drove the results or if there was another factor responsible for the differences seen.

This study was done in younger men, aged 18-35.  We cannot say for sure if the same results would be seen in women or what differences we would encounter with older subjects.  Often younger men respond differently then 40 or 50+ individuals.

The Take Away

So what lessons can we take away from this study?  First, if you are looking for a very straight forward strength training plan that can produce results the workout used in this research is a great model to follow.  The researchers did a nice job of choosing a program that is similar to what you would see in today’s gym settings for the average person looking to gain strength and size.  Yes we can change a few things around, I would.  It’s not perfect but it is a good model to think about.

Secondly, if you want to maximize the development of strength or size it may be time to stop following the high intensity model of high volume/low rest metabolic workouts that have become popular over the past few years.  Those workouts are still great and have a place in many programs but you have to think about what your training objective is.  If it is to improve anerobic work capacity and maximize calorie burn they may be the perfect choice.  If you are focused on maximizing strength or size gains you might want to slow down and take more rest between sets.

Should you take a full three minutes rest between all of your sets from now on?  Possibly but that creates a long workout and the reality is most people don’t have that much time to spend in the gym.  It is perfectly fine to shorten the rest time during your warm up sets.  Researchers have not reached any conclusion on the ideal rest period and other studies have found positive results at 2 minutes.  If you want to maximize your results but speed things up 2 minutes is probably fine for the average person.  Those at more elite levels should consider going a little longer.  And remember there were still positive improvements with subjects who utilized the 1 minute rest period.  The results may not be as great within an 8 week period but when you balance time demands into the equation it may be perfectly fine to stick with the shorter rest periods.  I would rather have someone come into the gym and rest for a minute or less between sets and get a good workout in then have them not workout at all because they didn’t have the time available to maximize their rest periods.

You can also consider utilizing the rest periods in a productive way.  No one says you have to sit around for 2-3 minutes between sets.  The trick is to make sure you are not loading the muscle groups that you are training.  While most people tend to not think about it, you also need to consider the impact on your nervous system of what you are doing.  If you are training legs that day, yes doing some sets of arms in-between does allow your legs muscles to rest but the nervous system is still being loaded and contributing to the buildup of fatigue. Don’t just think that training an unrelated body part means you are getting your optimal rest.  The nervous system is a key component to your training and any fatigue you put into it has to be considered.

If you are doing some sort of training split where you are not training your entire body that day you can consider doing some mobility exercises in-between sets that focus on the body parts you are not training that day.  Most of us can benefit from more flexibility and this approach ensures this important aspect of self care is not ignored as it often is.  Let’s face it, mobility work is the most commonly skipped part of a workout program and if you plan for it to be done during the workout between lifting sets you are far more likely to consistently get it done.

If you are doing a full body workout I suggest you focus on a specific movement pattern/body part first so as you move on through the workout you can then utilize the rest periods to do your stretching for the parts of the body you focused on in the prior training block.

There you go.  Time to rethink how long you are resting between sets and how you are utilizing those seconds.  There is no perfect answer yet but there are better answers.  Let your training objectives drive your decisions and most importantly, keep lifting.

Schoenfeld, B., Pope, Z., Benik, F., Hester, G., Sellers, J., Nooner, J., Schnaiter, J., Bond-Williams, K., Carter, A., Ross, C., Just, B., Henselmans, M. and Krieger, J.  (2016) Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy In Resistance-Trained Men. Journal of Strength and Conditioning Research. 30:7: 1805-1812.

What Type of HIIT Works Best?

HIIT (High Intensity Interval Training) works.  The jury has come back on that ruling and there isn’t much debate about it anymore.  You can improve aerobic fitness, strength, grow muscle, even turn on inactive genes.  Over the past few years study after study has shown the benefits of HIIT.  What is missing are some more conclusive answers to how different approaches to HIIT vary and which one you want to follow.

Doing repeated intervals on the bike or the treadmill is certainly different than using body weight exercises, which is again different then using external resistance like barbells and dumbbells.  Add in the challenge of how do you even compare the different modalities.  The variables you use to control the intensity on a piece of cardiovascular equipment (heart rate, time) may or may not translate to what you can control doing more traditional strength moves like squats, deadlifts and presses.  It is one thing to compare the length of two different bike intervals but how do you control and compare the intensity of a bike interval to that of a strength exercise?

Let’s not forget the impact different populations and their objectives have.  The average person looking for improved health doesn’t need the same program that someone looking to drop the maximum amount of body fat which is again different from what a runner/cyclist needs or what a strength athlete is looking for.  Everyone needs a combination of both strength and cardiovascular benefits but the mix changes depending on the person’s activities and objectives.

Androulakis-Korakakis et at. (2018) started to answers the question of which type of interval is best by comparing aerobically based intervals to resistance based intervals in well trained strength athletes.  The aerobic group performed 8 weeks of cycling intervals twice a week.  Each interval was for 30 seconds at 85% of maximum heart rate followed by 90 seconds of recovery at 50-60% max heart rate.  They performed 8 rounds.  The strength group used squats one day a week and deadlifts for their second training day.  They performed 8 rounds of the prescribed exercise with a weight equal to 60% of their 1 repetition maximum weight.  Each set was conducted until the subject reported a level of exertion equaling 80-90%.  This came to 8-15 repetitions over 16-30 seconds.  This group rested for 90 seconds between sets.  Both groups were allowed to continue doing their normal training the rest of the week.

If you guessed that after 8 weeks both groups saw improvements in their aerobic fitness then pat yourself on the back, you’re correct.  If you guessed that the group that did their intervals on the bike saw a significantly greater increase in cardiovascular fitness then you’ve earned a cookie.

When it came to strength improvements if you said both groups saw an improvement in strength then you area 3 for 3.  Now for a perfect score did was there a difference in strength improvements between the two groups?  No there was not.  Sorry to ruin your perfect record.  Both groups saw similar improvements in strength.  I know you had your money on the lifting group.

So what does all of this really mean?  Well, if you are a well trained strength athlete and you want to improve your cardiovascular fitness you can use strength based exercises to build your intervals.  The results won’t be as great as if you used aerobic exercises but they will be positive and meaningful.  Now what if you aren’t a well trained strength athlete?  I think you would be safe assuming the same general conclusion applies to you though the exact magnitude of the changes and the difference between the two different training approaches may be different, however they will probably both still improve your aerobic fitness and your strength.

I appreciate this study because it is one of the first to look at the practical question of what type of exercises we can use for our HIIT and how they differ.  The reality is in the gym all sorts of different movements are used to create HIIT circuits and trainers have been assuming they can create similar effects using body weight or strength exercises as they can with traditionally aerobic movements.  This study starts to provide some evidence to that question and clearly shows that the strength exercises will create improvement in cardiovascular measures, though not as great as if you use aerobic based intervals.  As always, you have to ask what your objectives are.

There are still some serious shortcomings to this study that keep us from implying any overly broad conclusions.  First, the study was done with trained strength athletes.  Their experience in the gym and the training state of their bodies means that they will have different responses then untrained individuals.  The subjects were also primarily in their early 20s and the reactions of middle aged and older exercisers could be different.  The subjects were also allowed to continue doing their normal training in addition to the prescribed HIIT.  Both groups showed similar improvements in strength and that could be the result of their other training and have nothing to do with the HIIT.  The squat/deadlift group also had a rather long rest period, far longer than is usually used in the gym for HIIT and this could be impacting the results this group saw.  I am also concerned about the testing choices used by the authors.  While valid, they are not as rigorous as other common techniques.

So what do these concerns mean to how I interpret this study?  I still like that they are examining the difference between different types of HIIT circuits.  I think the difference they found in cardiovascular improvements between the groups is suggestive of a more meaningful difference.  While only limited conclusions can be drawn this a good first step in helping us really figure out what works best for HIIT and what the differences are between different HIIT approaches.

If you are more concerned with aerobic improvements but still want some strength gains then you should be utilizing more traditional aerobic movements.  Not necessarily to the exclusion of traditional strength moves but certainly they need to form the foundation.  If you are more focused on strength and similar benefits this study would suggest it doesn’t matter what you use for your interval tough I think the subjects continuing their regular training hid potential strength advantages to the lifting centric approach.

Androulakis-Korakakis, P., Langdown, L., Lewis, A., Fisher, J., Gentil, P., Paoli, A. and Steele, J. (2018) Effects of Exercise Modality During Additional “High-Intensity Interval Training” on Aerobic Fitness and Strength in Powerlifting and Strongman Athletes.  Journal of Strength & Conditioning Research. Feb:32(2):450-457.