Researchers from the International Journal of Sports Physiology and Performance sought to assess the impact of two high intensity interval training (HIIT) programs on muscle strength and aerobic performances in rugby players. They recruited 36 players into the 8-week experiment and assigned them to three types of training groups:

• Strength and Short-Interval Training Group
• Strength and Sprint-Interval Training Group
• Strength-Only Training Group (No Cardio)

Max strength and power tests, peak oxygen uptake, and maximal aerobic velocity tests were conducted before and immediately after the training period to measure the strength and aerobic performance. The results showed that ALL groups in the experiment saw an increase in strength and jump-height performance.

However, peak oxygen uptake, was increased for those in the strength and sprint-interval group. However, the results also showed that slow concentric torque gains lowered (1).

Let's consider what that means when performing a bench press. During a bench press, the moment of concentric torque is when you've lowered the barbell to your chest and it's now time to press the weight back up. This is one of the most important parts of the movement. It's what we'd call "explosiveness."

What this study revealed is that when you perform cardio before weight training, your explosiveness is going to suffer, especially when you train with slower eccentric and concentric movements. Translation: If your primary goal is to build strength and power, avoid doing intervals before training.

Let's take a look at another study before drawing a consensus. In a 2003 publication by Sporer and Wenger, the study group sought to put a nail in the coffin of the cardio timing question by recruiting 16 male athletes who were strength training 2-3 times per week six months before the study began. Pretty typical training for the average gym-goer.

The 16 subjects were initially divided into a high-intensity aerobic group or a submaximal aerobic group on cycle ergometers. In other words, half of the test subjects did high-intensity interval training where the others trained in the dreaded "moderate intensity cardio zone" before performing a resistance training workout where they did four sets of bench presses and leg presses with 75% of their 1RM until failure. Sounds fun.

In the leg press, those who only had a four and eight-hour break noticed a drop in performance. At 24 hours, there was no drop in strength production.

In the bench press, there was no difference at all – the intensity of training didn't matter in this study, but the recovery time between bouts of training did.

Translation: It's best to separate your cardio and resistance training by at least eight hours to prevent a decrease in strength performance.

A recent meta-analysis in the Exercise Sports Science Review sought to discover whether hypertrophy (rather than strength) would be adversely affected by the timing of cardio. Further, they wanted to discover what type of endurance training would be the most effective for building muscle if done before lifting.

Not surprisingly, researchers concluded HIIT cardio to be the best form of training to improve both strength and size, yet athletes involved in sports predicated on developing force quickly (namely power sports) should be leery of introducing frequent concurrent training into their program.

Enough whiteboards and lab coats. Here's what this means for your training:

• If choosing between HIIT and traditional steady state cardio, HIIT is your best option to minimize negative effects on building muscle and strength.
• Separate cardio workouts by at least eight hours to optimize the hypertrophic and neural adaptations to strength training. The longer the better, especially if you have lower-body training planned.
• Low-intensity cardio like walking is always a good option to improve recovery and accelerate fat loss, yet it's often neglected and overlooked. A simple strategy is to set a step goal of 8,000 to 10,000 steps per day and consider that your daily low-intensity cardio.

Here's a three-day a week plan. Now, you can do a training program in which you're at the gym 5-6 days a week, but I recommend keeping your concurrent training days to three times a week max to make sure you give your body proper recovery time.

Working out three days a week means that you'd do two workouts a day, however. Remember, the name of the game with cardio is to keep it separated from your lifting by at least 8 hours. So you could either do it later that same day or do it the next day, which would mean working out 6 days a week alternating between cardio and lifting.

Your morning and evening workouts can be flipped. You can do cardio in the evening or in the morning, as long as you swap it for the other daily workout.

Monday Morning Workout

Monday Evening Workout

Do 12 rounds of stationary cycling: 30 seconds on (max effort) 60 seconds off (recovery effort).

Wednesday Morning Workout

Wednesday Evening Workout

Do 12 rounds of jump rope: 30 seconds on (max effort) 60 seconds off (recovery effort).

Friday Morning Workout

Friday Evening Workout

Do 12 rounds of sprints: 30 seconds on (max effort) 60 seconds off (recovery effort).

Proper nutrition and recovery will determine how much progress you make with this or any other program. If this is your first go at a concurrent training program, then increase your caloric intake if building muscle and strength is your primary goal. Fuel your workouts with Plazma™ before and during training.

The additional work should improve fat loss by helping you burn more calories and improve energy substrate utilization. In other words, you'll break down fat and carbs into usable energy more effectively.

1. Robineau, J, et al. "Concurrent Training in Rugby Sevens: Effects of High-Intensity Interval Exercises." Advances in Pediatrics., U.S. National Library of Medicine, Mar. 2017, PUBMED.
2. "Concurrent Training." The Science of Breathing
3. Wilson, J M, et al. "Concurrent Training: a Meta-Analysis Examining Interference of Aerobic and Resistance Exercises." Advances in Pediatrics., U.S. National Library of Medicine, Aug. 2012, PUBMED.