How long have your workouts followed the exact same format? You do an exercise for a predetermined number of sets and reps, and then move onto the next move. Maybe sometimes you get crazy and combine exercises into a superset or circuit.

There’s nothing wrong with this approach. In fact, this style of training is the most efficient way to build max strength and power.

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But maybe you need something else—something that challenges both your strength and endurance. Or you just need to add some variety to your training. If so, try incorporating timed sets into your training schedule.

Timed sets can involve one or more exercises. Rather than performing a move for a specified number of sets, complete as many sets as you can  within a given time frame, resting only as needed. It’s you versus the clock.

This method is called density training. Each time you perform the same workout, your goal is to do more sets than you previously did in the same period of time, thus increasing the density of the workout. You don’t change weight or sets and reps, you simply try to do more work. As a byproduct, your strength and endurance will improve.

Competing against yourself and beating your previous results guarantees that you will make progress in your training. If you make even a slight improvement, you’re doing more work than you did before and making gains.

Also, timed circuit workouts are great because they are so efficient. You know exactly how long your workouts will take, allowing you to get in a great workout in a short amount of time whenever you’re in a crunch.

Todd Durkin’s Timed Circuit Workout

You might choose one exercise and perform as many reps as possible in a specified time as a finisher at the end of your workout. An example of this is the Two-Minute Squat Challenge.

Or, you can create a complete workout with several timed circuits, as shown in the plan below. Created by Todd Durkin, owner of Fitness Quest 10 (San Diego), this routine was performed by elite NFL athletes Drew Brees, Darren Sproles and Gerald McCoy as part of their off-season training program.

It’s not for the faint of heart. “This workout is a beast,” says Durkin. “The pro guys love it, but it’s tough because you’re combining conditioning and strength work. [At] each station, you have eight minutes to do as many rounds as you can. It’s a lot of metabolic work. When we hit those circuits, it’s all out intensity. The intensity plays a huge role in the success of the workout.”

Durkin’s pro guys are able to complete each circuit four or five times. But they are at an elite level. When you first try this program, go for two or three rounds. As your need for rest decreases, you’ll be able to increase the number of rounds.

Best of all, this workout should take you no more than 45 minutes to complete, including a dynamic warm-up and cooldown.

Perform each circuit for eight minutes, completing as many sets as you can, resting only as needed. Rest for 1-2 minutes between circuits.

Circuit 1

• Med Ball Push-Ups:  15 reps + 10 sec. hold
• Scissor Jumps : 20-30 reps
• TRX Power Pulls or Seated Rows: 8 reps each side or 12 reps
• Double- or Single-Leg RDL: 12 reps or 8 reps each leg

Circuit 2 

• Treadmill Sprints: 2×10-20 sec.
• Supermans or Side-Ups: 10 reps
• Physioball or Ab Wheel Rollouts: 20-30 sec.

Circuit 3

• Forward to Reverse Lunge: 20 reps
• Lat Pulldowns or Pull-Ups: 10 reps
• Overhead Tricep Extension and Press: 10 reps each
• Bicep Curls: 8-12 reps

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