A Guide To Rest Times For Strength Training: 300 Seconds

300 seconds = 5 minutes. Why is this number and the resultant math to convert it to minutes important? This length of time, to those of you familiar with training with kettlebells and other metcon training methods, will seem like an eternity when told that is how long you should rest between sets when training for strength.

But according to a 2009 study on rest intervals and strength training:

Resting 3-5 minutes between sets produced greater increases in absolute strength, due to higher intensities and volumes of training. Similarly, higher levels of muscular power were demonstrated over multiple sets with 3 or 5 minutes versus 1 minute of rest between sets. Conversely, some experiments have demonstrated that when testing maximal strength, 1-minute rest intervals might be sufficient between repeated attempts; however, from a psychological and physiological standpoint, the inclusion of 3- to 5-minute rest intervals might be safer and more reliable. [Source]

My observations of and experimentation with hundreds of athletes and clients in addition to my own powerlifting training over the years support the above findings.

Rest intervals for strength training


As a powerlifter, resting for five minutes between my work sets was easy. Rack the bar, load the weight for the next set and/or check the collars for tightness, sit down, wipe my forehead, grab a sip of water, and set the timer for five minutes.

The first two or three minutes were usually reserved for slowing down my breathing, talking shop with others around me, and just chilling. The last two minutes before moving into my next set were reserved for my mental state – making sure I was ready. You see, my goal when performing those work sets was not only to have quality reps, but also to achieve the quantity I had planned for that training session.

For example, if my training plan called for 4 sets of 5 reps at 82.5% 1RM, then my goal was to get all 20 reps. Good quality – maintaining good form and technique throughout all the reps and never sacrificing my body – was a must. But so were the 20 reps.

What helped me accomplish this were those 5 minutes – 300 seconds – between sets. This allowed most of the physiological changes that occurred during the previous set to return to normal. If I needed an extra minute or two, I took it. Again, my goal was 20 quality reps. All of them. As a result, these work sets alone might take me 20-25 minutes to complete.

Knowing this time requirement for the training session, I made sure I had enough time scheduled to complete the work sets as well as the rest of the session. Plan for it ahead of time. That way you don’t rush through your training and potentially make costly mistakes with your body.

SFL Cert StrongFirst


During the SFL Barbell Instructor Certification, we spend four hours on the programming lecture. During part of the lecture, I discuss the 300-second period. Most of the students at the SFL Cert come from a background of kettlebells, metcons, and strength endurance where rest periods of ten to thirty seconds are normal. The SFL and the training required to pass the associated strength and technique tests usually mark the first time they have seriously trained with the barbell.

These students quickly realize that ten to thirty seconds of rest won’t cut it when training for strength and expecting results. So when I mention that it is best to take three to five minutes between sets to almost or completely recover and therefore make the most of the succeeding set, I get looks like I just told them I was from outer space.

For some trainees, this time length seems like an eternity. They ask, “What am I going to do during that time?” or “Can I do some mobility exercises?” or “Starbucks, anyone?”

While all good questions, any question regarding what to do during the rest period should receive the same answer: rest. And rest some more. Maybe go fill up your water bottle. You shouldn’t have to worry about a bathroom road trip as that should have been done prior to the work sets starting. In addition, unless you are using your cell phone calculator to add up the weights on the bar, turn off your cell and don’t use it, look at it, or even touch it during your training session.

Your mission, should you choose to accept it, is to complete all the reps of your work sets with quality – down to the last rep of the last set. As we say in our gym, “Last rep, best rep!”



  1. Rest 180-300 seconds (3-5 minutes) between work sets when training for strength, regardless of the implement. I lean more toward the 300-second time span.
  2. Plan for a potentially longer training session in your personal schedule so you don’t have to rush through and get sloppy.
  3. Use a timer for your rest period. My OCD personality likes to know how much time is left. Plus, it keeps you on schedule.
  4. Tell your training buddies to leave you alone when it gets closer to your work set, i.e. the last 2 minutes of rest. This is your time to get in the zone and get mentally ready to properly attack the next set.
  5. Make sure you have good posture and your extremities are relaxed when sitting in your chair during the rest period.
  6. Make sure you have good spotters to help you during these work sets if needed and if the movement allows them – especially during the later work sets.
  7. These rest periods also apply to training with kettlebells, e.g. kettlebell military press, strongman work, etc.


  1. Don’t do the next set after 1:36 of rest because you feel ready. Trust me, take the 3-5 minutes. If your training plan calls for more than one work set, use the entire length of rest time.
  2. Don’t perform any calisthenics, weird 70s disco moves, mobility exercises, or any other movements except walking and loading the bar for the next set. Rest!
  4. Don’t give up on this longer rest period when training for strength. You will get used to it and appreciate it, especially when you see the results.

Written By Dr. Michael Hartle