Like many other guys over the age of 35 who work full-time in the fitness industry, my interest in exercise was sparked by the Arnold Schwarzenegger movies of the 1980s. For the Christmas of my junior year in high school, I received an Olympic barbell set and a burly weight bench and immediately set them up in my basement. Like many teenage boys, I was interested in weight training for the purpose of developing a ripped physique. You can probably guess the first book I bought: Arnold's Encyclopedia of Bodybuilding.

Flash forward many, many years (and more than a few gray hairs) later and even after earning a couple of certifications and a master's in exercise science, one of the most important rules of training for results comes back to a principle tenet of Arnold's book: The volume of the workout program and frequency of training sessions play a critical role in stimulating muscle growth. If you have clients who want to train for muscle size or definition, volume and frequency are two essential variables to consider when designing an exercise program.

Keep in mind that exercise is a physical stressor and, depending on other stressors affecting your client, it can take some trial and error to find the right combination of volume and frequency. Training too often or with too much intensity and not allowing the proper rest between sessions could cause either an overuse injury or lead to overtraining, both of which can significantly limit a client's ability to achieve his or her fitness goals.

Volume refers to the total amount of physical work performed in either a single workout session or over the course of an extended exercise program. In general, training volume is considered to be the product of the intensity—the specific amount of weight used per set, the number of repetitions performed and the total number of sets in a workout. Volume can also account for the time under tension or tempo (speed) of the exercises. Lifts at a slower tempo will place more tension on muscle tissue and can be considered a component of the total training volume for an exercise program. When it comes to endurance or energy system training, volume generally refers to the distance covered, the tempo or speed of movement (e.g., sprint, race pace or steady tempo) and, if necessary, the number of repetitions (e.g., sprint repeats). 

Here is a sample workout for a client interested in increasing leg strength:

*Intensity—the amount of weight used equals the client's 8-rep max for that lift.

Training Frequency

Frequency refers to the number of training sessions per a specific period of time such as week, month, quarter or year. The frequency of workouts should be based on an individual client’s training goals, experience and current fitness level. Clients just starting a workout program for the first time or restarting after an extended layoff should set an initial process goal of exercising only two to three times per week. Oftentimes, a new client may claim to want to work out every day; while laudable, this is an unrealistic goal for someone with a history of being sedentary. It also can lead to discouragement if he or she has to miss a workout for any reason—the client may see it as a failure, which could lead back to the behavior of skipping the gym altogether. Helping a new client set a realistic goal of exercising twice per week and once on the weekend increases the likelihood that he or she will meet that goal. Once that goal is achieved and the client feels successful, other goals can be established. The key to losing 50 pounds is losing the first two (then the second two, the third two and so on). Helping clients set small, realistic goals can help establish little victories and develop habits that will last for a long time. 

Other variables that help determine training frequency are intensity and volume. In general, there is an inverse relationship between training volume and intensity—when the intensity of a workout is high, either from heavier loads or more explosive movements, then the volume and frequency of workouts should be lower. When the exercise program features higher-intensity loads, or exercises that include more challenging movement patterns or movement velocities, increased demands are placed on the neuromuscular system that requires longer recovery periods between the workouts to ensure adequate adaptation and recovery. High-intensity workouts place a significant amount of mechanical stress on muscle tissue and metabolic demands on the anaerobic energy pathways; therefore, fewer reps, sets and training sessions per week should be performed. High-intensity workouts require rest time to allow the nervous system to recover and the muscular system to repair and refuel. Too much high-intensity training in a short period of time could lead to an overuse injury or overtraining.

Sample Training Frequency for One Week of a High-intensity Weightlifting Program

In the program above, each day after a heavy day is either a rest or active recovery day, to ensure that the nervous system will be able to recover from fatigue and the muscles will have enough time for protein re-synthesis and glycogen replenishment.

On the other hand, when training intensity is relatively low, like for endurance training, the number of repetitions and sets can be higher and the rest period between workouts can be shorter. Endurance training uses the long-term mitochondrial energy pathways, which need less time for replenishment and refueling between submaximal workouts. When the exercise program features a lower volume or lower-intensity exercise, less time is required between exercise sessions for adaptation and recovery. The fitness level and goal of each individual client will determine the volume and frequency of his or her training program.

Guidelines for Resistance Training Frequency Based on Training Experience

Monitoring Volume and Frequency

Periodization is the science of applying training volume and frequency. In short, periodization organizes a training program into specific blocks (periods) of time that alternate between high-intensity workouts and lower-volume and frequency and more frequent lower-intensity workouts with higher repetitions ranges. There are countless way to organize periodized programs, from linear where each block of time becomes a little more challenging, to undulating where the workout intensity changes from day to day. Think of every client and training session as a sort of mini-experiment—if you want to develop training programs that consistently deliver results, it is important to keep accurate records of clients’ programs to identify the most effective exercises and workouts for specific outcomes.

For many clients with goals related to general fitness or improving health, monitoring training volume might not be that important. However, if you are working with clients who have specific performance, weight-loss or aesthetic goals (e.g., training for an obstacle course race, losing weight after the birth of a child or preparing for a physique competition), recording and monitoring training volume is extremely important to identify what works and what might need to be adjusted for future training plans. For example, if you train a lot of women preparing for their weddings, you might want to have a record of the workouts that your clients felt gave them the best results.

Another benefit of writing down clients’ workouts—especially the intensity, reps and sets—is that it gives you a way to monitor the applied training stress. Training intensity records combined with daily feedback from your clients regarding other stressors will help you know when to increase the training intensity during periods of reduced outside stress and decrease intensity when they might have higher stress levels from deadlines or increased demands at home. If a client is going through a period of stress at work or home, it could affect his or her sleep patterns or dietary habits, both of which could interfere with the ability to properly recover from a training program.

Consider, for example, a mother with two school-age children home for the summer. She will be busy organizing her kids’ activities and may not have as much time for training, so she would need a maintenance program. Once her kids are back in school, she may return to a more consistent schedule that gives her the ability to recover from harder, more intense training sessions. A second example would be an accountant who will be slammed at work for the six weeks prior to the April 15 tax-filing deadline. During this high-stress period, the accountant will need lower-intensity workouts to help reduce the stress from work. Once tax season is over it would be appropriate to increase the training intensity to work toward specific goals.

The reason why Arnold and other bodybuilders follow split-routine programs where they focus on just one or two body parts per training session is to allow their muscles sufficient time to repair and recover between workouts. If you look at the training program of any top performer, whether an athlete or a physique competitor, you will see how they use periodization to adjust volume and frequency of the training intensity. Knowing how to adjust frequency and volume to develop periodized programs means that you are more than just a trainer to your clients—you become a fitness specialist who can provide effective workouts throughout the entire year. This helps ensure you remain relevant in their lives and retain their business. However, real success from an exercise program requires the knowledge of how to structure rest and promote recovery, which will be the topic of the next and final part in our series.

Part 1: How to Select the Right Exercises for Your Clients

Part 2: How to Select the Right Intensity and Repetions for Your Clients

Part 3: How to Select the Right Sets and Tempo for Your Clients