I have a client who has recently taken a six week break from exercise due to overseas travel. On her arrival home, she had increased weight, body circumference and body fat percentage. We all know that ceasing any exercise program will lead to the above results. What I would like to know is how much inactivity is required before you start to see a decrease in cardiovascular fitness and muscular strength and an increase in body fat percentage circumferences.
This is a very difficult question to answer due to individual factors such as: Was your client on vacation? Did she only eat at restaurants, which are full of hidden calories? Was her stress level higher than normal? How different was her activity level on the trip? What do you mean by muscle strength – absolute or functional? What is your client’s current level of fitness (i.e., a marathon runner will decline much differently than a de-conditioned client)?
Below is a brief review of studies that may assist in answering your question. The information is not exact to any one client. Therefore, please apply with an analytical mind set.
- Studies showed that when resistance training ceases or is drastically reduced, strength declines at a slower rate than the rate at which strength increased. In other words, it takes longer to lose strength than it does to gain it.
- In most instances, complete termination of strength training results in an immediate decline of strength. It is important to note that the populations used in this study were elite athletes training with high levels of intensity.
- Collectively, the information offered on both short and longer periods of rest indicates that in general, strength decreases do occur but at variable magnitudes. The rate of strength loss may depend in part on the length of the training period prior to rest, the type of strength test used and the specific region examined.
- We all know that training results in an improvement in exercise capacity, and inactivity leads to deterioration. Deterioration will depend on the person’s prior fitness level and the level of inactivity.
- Research reveals that bed rest (as inactive as you can get) effects most aspects of physiological function. The studies overwhelmingly show that bed rest leads to changes in the body’s functional and psychological state, with some of these changes occuring during the first few days.
- The harmful effects of bed rest are largely due to a decrease in hydrostatic pressure within the cardiovascular system, a reduced energy expenditure due to inactivity, a decreased loading of the muscle and skeleton, a change of diet and psychological stress.
- Decreases in maximal O2 consumption and work capacity range from one to 26 percent, depending on the type and duration of inactivity.
- If the energy in is more than the energy out, your client will gain weight. If she is not active, there’s a great chance the weight gain will be fat and not muscle.
I hope this helps. The effects of inactivity are reversible with the proper exercise programming. Start back.... but slowly!