Professional athletes frequently exercise and compete at extremely high levels of intensity, and the conditioning coaches who work with them apply the latest exercise science research to help them achieve an optimal level of performance. Additionally, many professional athletes invest a significant amount of time and money in post-exercise recovery strategies, as the past decade has seen a significant increase in research on specific techniques to help athletes recover quickly after strenuous workouts. While your clientele may not be competing at a high level, they nonetheless can benefit from these recovery techniques and protocols in the pursuit of their health and fitness goals, while also lowering their risk of injury. Fortunately, a wide range of approaches is available, many at no cost to you or your clients.

Exercise Is Stress Imposed Upon the Body

Exercise is physical stress applied to the tissues and physiological systems of the body. The intensity, type and duration of the exercise determines whether a specific strategy could help accelerate the recovery process to prepare for the next workout. When an exercise session is completed, the body needs to replace the energy used by muscles, remove metabolic byproducts that could reduce force production, and repair any damage done to the structures of muscle fibers and connective tissues. When clients exercise at a low-to-moderate intensity, recovery strategies are generally not needed because they have not experienced a significant amount of physical stress. In fact, a low-intensity workout is one strategy that could help clients recover from the stresses imposed by a higher-intensity workout on a prior day. 

High-intensity exercise—specifically resistance training to the point of fatigue and high-intensity interval training (HIIT) used to improve aerobic capacity—causes a tremendous amount of stress on various physiological systems of the body, including the muscular, nervous, respiratory and endocrine systems. It’s these systems that require the time to recover to be adequately prepared for the next exercise session. 

High-intensity exercise results in two types of overload on muscle and connective tissues: metabolic and mechanical. Metabolic overload is the process of depleting muscle cells of available energy. Type II muscle fibers store glycogen and adenosine triphosphate (ATP) to fuel contractions; high-intensity exercise depletes these resources, and it takes time to replace them and ensure muscles are properly fueled for the next workout (or competition). Mechanical overload creates physical damage to the protein structures of individual muscle fibers and connective tissues. During the recovery process, myoblasts and proteins help repair tissues damaged by the workout. High-intensity exercise results in varying levels of mechanical damage or metabolic fatigue, and time is needed for the body to repair and refuel. It is these workouts that require a specific approach to recovery so that a client can experience optimal adaptions while allowing the body to rest and prepare for the next workout. 

The Process of Recovery 

Homeostasis is the normal operating condition of the human body while in a state of rest. Exercise requires energy metabolism and muscle force production, which disrupt homeostasis. The period after exercise is when the body goes through the process of returning to homeostasis. During the post-workout recovery period, muscles are expending energy to replace energy—specifically, the glycogen and ATP used for anaerobic metabolism—repairing tissues damaged during exercise and removing metabolic by-products, all of which can be identified by elevated levels of oxygen consumption technically known as the excess post-exercise oxygen consumption (EPOC). The body burns approximately 5 calories of energy to consume 1 liter of oxygen. The EPOC effect helps to burn calories even after the workout is over because muscle tissues are consuming more oxygen to replace the oxygen deficit created during non-steady-state exercise, remove and reconvert lactate, reload hemoglobin/myoglobin and repair tissues. 

In a comprehensive review of the effectiveness of different recovery strategies, Dupuy and colleagues described the recovery process as a “return to homeostasis of physiological systems following metabolic and muscle damage induced by exercise.” The purpose of applying a specific recovery strategy is to reduce the amount of time it takes to restore homeostasis while enhancing the body’s ability to prepare for the next exercise session.

To speed up the recovery process after a high-intensity exercise bout, the goal should be to increase the heart rate to promote blood circulation for the purpose of delivering oxygen, nutrients, satellite cells and tissue-repairing hormones to muscles, while removing by-products such as creatine kinase (an enzyme produced in response to damage to muscle proteins) and inflammatory agents such as interleukin that could impair the tissue-repair and energy-replenishment processes. 

Specific Strategies for Recovery Should Accompany High-intensity Workouts

One of the most important results of an exercise program is the ability to be physically active every day. High-intensity exercise has been one of the most popular fitness trends because it can help deliver results for both aesthetic and health goals. The challenge, however, is that the same high-intensity workouts that deliver results may also cause soreness and limit the ability to exercise the following day, thereby reducing the overall amount of physical activity an individual might perform in a week. In addition, too many high-intensity workouts without the proper time for rest and recovery could result in overtraining syndrome, which may limit the effectiveness of the workouts, weaken the immune system or cause an injury, none of which are desirable outcomes. 

High-intensity workouts to the point of fatigue create both metabolic and mechanical overload. When designing high-intensity workouts that deliver the results your clients and group workout participants want, it is also necessary to identify effective techniques to help them recover once the exercise session has been completed. Certain methods presented in the table below, such as wearing compression clothing, sitting in a cryogenic chamber, applying a percussion gun to muscles, using an infrared sauna or getting a massage, may help accelerate the recovery process, but these come with additional costs and may not be accessible for many clients. If you work in a full-service health club with amenities such as a hot tub, sauna or steam room, urge your clients and class participants to use them after a high-intensity workout to help facilitate the recovery process. 

A general strategy to promote the recovery process includes applying various methods that can increase the heart rate, elevate tissue temperatures or reduce inflammation. Table 1 describes several recovery strategies and provides specific methods that range from readily available to those requiring specific equipment. Based on available research, the table also includes specific methods that can help promote the recovery process.


Table 1. Methods of Recovery and Their Application


Method of Recovery 


Increasing ambient temperature to elevate tissue temperature: As tissue temperature elevates, heart rate will increase in order to help with thermoregulation; it’s this increase in heart rate that helps promote recovery. As Hausswirth and Mujika discuss in their book, Recovery for Performance in Sport, infrared rays in an infrared sauna produce heat that molecules can partially absorb. Because the heat affects the cells directly, infrared saunas operate at a lower temperature when compared to traditional saunas, allowing for a more comfortable experience.


  • Infrared sauna
  • Standard sauna
  • Hot tub 
  • Steam room 

Applying extremely cold temperatures: There are two prevailing theories about how cryotherapy promotes recovery. The first is that exposure to extremely cold temperatures causes blood to rush to the vital organs to keep them protected; as the cold is removed and the body returns to normal temperature, the blood will return to the extremities, bringing the necessary oxygen, nutrients and cells. The rapid application of cold causes the sympathetic nervous system to release epinephrine and cortisol, which increase circulation.


The second theory has to do with the fact that cold could help reduce inflammation caused by mechanical damage to the tissue structures. Inflammation increases pressure on the nerve endings that sense pain; when inflammation is lowered, explains Hausswirth and Mujika, so is the perception of pain.


  • Cryotherapy
  • Exposure to extremely cold temperatures (–110 to –140° C or –166 to –220° F) for 2 to 4 minutes; or exposure to an ice bath for 15 to 20 minutes


Applying pressure to muscle tissue to assist in circulation or reduce tightness: The Golgi tendon organs (GTO) are sensory nerve endings where muscles attach to tendons. Applying pressure to muscle fibers creates a reflexive response that relaxes and lengthens muscle fibers, which helps to reduce overall tightness. This method also elevates tissue temperature, which increases blood flow. 


Compression clothing applies a steady source of pressure to muscle tissue that could help increase circulation by promoting venous return of blood to the heart. Compression clothing can also elevate tissue temperature, which could help reduce the overall perception of soreness.


Performing body-weight exercises in multiple planes of motion: Moving in multiple directions elevates the heart rate while increasing tissue temperature. The first two phases of the Muscular Training component of the ACE Integrated Fitness Training® (ACE IFT®) Model—Functional and Movement Training—feature primarily low-intensity body-weight exercises that are ideally suited for mobility workouts to promote active recovery. 


No-cost Recovery Solutions

It is worth noting that the most effective method of recovery doesn’t require any additional investment from the client, as it is based on a mindful approach to how exercise programs are designed and implemented. The recovery phase is when clients experience the actual physiological changes to their bodies, which explains why so many tools have been developed to promote this process. However, other than the costs associated with paying for personal-training sessions or group workout fees, the recovery method that could produce the greatest benefit is simply getting an appropriate amount of rest either by alternating the intensity of exercise or getting more sleep. Rest is one of the most effective recovery methods and one that can be achieved by either periodizing the intensity of workouts or by going to bed earlier every evening.

Sleep, the Ultimate Recovery Method

The National Sleep Foundation, an organization of medical professionals and researchers who study and promote the benefits of sleep for achieving optimal health, recommends adults sleep seven to nine hours per night. Sleep allows muscles to repair damaged tissues and replace spent energy. In addition, growth hormone, an anabolic hormone produced during stage 3 of non-rapid eye movement sleep, helps to repair muscle and connective tissues damaged during exercise. The longer one sleeps, the more time they give their muscle tissues to regenerate and grow.

When clients can increase their sleep time by an hour per night, it is like achieving an entire extra night’s worth of sleep over the course of a week. To learn more about sleep and how it could benefit clients, refer to the following articles that explain how to improve overall sleep hygiene:

Does Sleep Help You Lose Weight?

The Power of Sleep

Teach Your Body to Sleep Better

Periodization involves organizing the variables of exercise program design to alternate between low-, high- or moderate-intensity workouts. The purpose of periodization is to adjust the overall volume of metabolic or mechanical overload, while ensuring an adequate amount of rest between exercise sessions to allow for the recovery process to produce the desired adaptations. The greatest benefit of periodization is that it uses lower-intensity activity or rest to allow the body to adapt to the physically demanding exercise performed during exercise. You can use periodization to structure periods of lower-intensity exercise or rest that could help your clients reach their goals.

The ACE Integrated Fitness Training® (ACE IFT®) Model) features two primary components: Muscular Training and Cardiorespiratory Training, and each of these components is further divided into three specific phases based on the intensity of exercise. The three phases of the Cardiorespiratory component—Base, Fitness and Performance Training—are organized based on intensity as determined by the first and second ventilatory thresholds (VT1 and VT2). VT1 is the intensity of exercise where muscles transition from aerobic to anaerobic metabolism to produce the energy for force production. VT2 is the indicator of the onset of blood lactate accumulation, a marker of how much metabolic by-product is generated from anaerobic exercise. Exercise below VT1 relies on aerobic metabolism for energy and is lower in intensity than exercise at or above VT2. 

The three phases of the Muscular Training component of the ACE IFT Model—Functional, Movement and Load/Speed Training—are organized based on the magnitude or velocity of muscle force production. The first two phases, Functional and Movement Training, feature body-weight exercises to enhance the stability and mobility of major joints in the body, as well as to improve overall coordination and movement efficiency. The third phase, Load/Speed Training, relies on using high amounts of external resistance to increase overall muscle-force production or explosive movements to enhance the rate of force production. The Load/Speed Training phase uses heavy weights or explosive movements and should be considered high-intensity, whereas the Functional and Movement Training phases use primarily body-weight movements and are considered low-to-moderate intensity. 

Undulating periodization, also known as non-linear periodization, is well suited for general fitness clients because it allows for frequent changes in intensity and volume. Exercise program design based on the concept of undulating periodization means alternating between high-, moderate- and low-intensity workouts over the course of a week, allowing a client who feels they must exercise every day to do so but at different levels of intensity to ensure appropriate recovery. 

It may be helpful to consider different phases as indicators of stress load and corresponding rating of perceive exertion (RPE) on a 10-point scale:

  • Functional and Base Training (3−4)
  • Movement or Fitness Training (5−6) 
  • Load/Speed and Performance Training (7−10) 

Workouts can be organized so that a high-stress day is followed by a low-to-moderate stress day. When exercise intensity fluctuates from day to day, the lower-intensity workouts promote active recovery from the higher-intensity workouts on the preceding day. 

Undulating Periodization 

Undulating periodization alternates between high-intensity workouts to create mechanical or metabolic overload and lower-intensity exercises that help promote active recovery from more stressful workouts. Depending on a client’s individual goals and fitness level, they might perform two to three high-intensity workouts from the Load/Speed or Performance Training phases, two to three moderate-intensity workouts from the Movement or Fitness Training phases and one or two workouts from the Functional or Base Training phases. For clients who have time constraints, this model allows for at least one Load/Speed or Performance Training workout, one Movement or Fitness Training workout and one Functional or Base Training workout each week. 

The sample program presented in Table 2 is for a client interested in managing a healthy body weight. The strength-training sessions focus on high-intensity strength exercises to promote muscle growth and the other workouts utilize the group fitness program to offer options for cardiorespiratory and mobility-based exercise throughout the week. Group fitness classes can be a great resource for helping clients reap benefits from overlooked modes of exercise like mobility. 

Table 2

Weekly Workout Schedule – Applying the ACE IFT Model to Undulating Periodization









Low-to-moderate intensity exercises from the Functional, Movement or Base Training phases 


3−4 RPE

High-intensity exercises from the Load/Speed or Performance Training phases


7−10 RPE

Moderate-intensity exercises from the Functional or Fitness Training phases


5−6 RPE

Low-to-moderate intensity exercises from the Functional, Movement or Base Training phases 


3−4 RPE

High-intensity exercises from the Load/Speed or Performance Training phases


7−10 RPE

Rest, or low-to-moderate intensity exercises from the Functional, Movement or Base Training phases 


3−4 RPE

High-intensity exercises from the Load/Speed or Performance Training phases


7−10 RPE 

Note: Rating of perceived exertion are given using the 10-point scale.


While product- and service-based recovery methods have been shown to be effective, these may be cost-prohibitive for some clients. However, a mindful approach to exercise program design based on the science of periodization has also shown to aid in the recovery process. Encourage your clients to increase the amount of sleep they get each night or to improve their overall sleep hygiene, as these efforts could provide the additional recovery needed to ensure optimal adaptations to an exercise program. When it comes to recommending recovery strategies to clients, remember that the end of one workout is the beginning of the next. Proper recovery strategies allow clients to be fully prepared for each workout so they can achieve the best results possible.