"Triple" Progressive Overload Process

NSPA believes that the client and the trainer needs to fully understand the fundamentals of the overload process and the "triple progressive" overload process in order to achieve maximum strength results from the HIT system.

Progressive overload process - this process involves the breakdown of muscle fibers (micro trauma) with increased stress (overload stimulus) that is greater than the previous workout. After overloading the muscle there must be appropriate rest and recovery in order for the muscle to completely heal and repair. If rest and nourishment are maximized the muscle tissue will adapt (adaptation) by getting stronger and larger (hypertrophy).

Variation Overload:

1)    Under-dose overload: If a client does not stimulate the muscle with an overload that is equal or greater than the previous workout the muscle will not respond with increased strength. It will only respond to the level at which it is stimulated. In fact, the muscle will regress to the level of stress that is applied.

2)    Maintained -overload: If the client stimulates the muscle with the same stimulus or overload as the previous workout the muscle tissue will remain at the same level of strength.

3)    Increased-overload: If the client stimulates the muscle tissue with a greater stimulus than the previous workout, the muscle tissue will progress with increased strength.  

4)    Overdose-overload: Too much stimulus results in excessive breakdown of muscle tissue and creates overtraining complications.

HIT - Triple Progressive Overload  

The "double progressive" overload technique involves adding weight and/ or increasing the number of reps from the previous workout. The HIT system utilizes the "double progressive" technique and then adds a third component, time under tension. The third component then creates the "triple progressive" overload process. This is essential for direct accountability of accurate strength gains, perfect reps and eliminating non-productive sets.

Triple Progressive Overload Technique

1.      Increase Time under Tension

2.      Increase Reps

3.      Increase Weight & Do Not Cheat!

The "triple progressive" overload technique reinforces the significance of the controlled rep and of the strength accountability necessary to accurately assess strength gains. In order for the HIT system to be maximally successful the client and trainer must understand how to implement the "triple progressive" overload process. The following is a detailed description of the three variables involved:

1) Increase Time under Tension - Time under tension refers to the amount of time the muscle(s) is being stressed (overloaded) during a set. The muscle should never relax at any time during the entire set. The recommended time under tension per rep is between 6 to 8 seconds. Therefore, if an client sets a rep range between 10 to 12 reps, the time under tension range will be between 60 seconds (10 reps x 6 sec.) and 96 seconds (12 reps x 8 sec.). Example: a client executes 10 perfect reps to MMF on the leg extension machine, with 100 pounds, and the total time under tension was 60 seconds. The average rep speed is then calculated by dividing the 10 reps into 60 seconds, which would equal 6 seconds per rep. The recommendation for the next workout would be to stay with the 100 lbs and increase the reps to 11 or 12 and increase the time under tension to 66-72 seconds. A minimum speed of 6 seconds per rep is acceptable under HIT guidelines.

The following is an example of a client that performs more reps but actually less work. During Monday's workout the client uses 100 pounds on the leg extension machine and executes 10 reps in 70 seconds. The average rep speed was 7 seconds. The next workout, two days later, the client uses 100 pounds again on the leg extension and performs 12 reps in 60 seconds. The average speed per rep is 5 seconds. This is below the acceptable rep speed guideline for HIT, and was 10 seconds less than the time under tension performed on Monday. The client is convinced that they got stronger due to the fact that they performed two more reps than in the previous workout. However, because the time under tension was 10 seconds less, and the resistance was the same, the client did not increase the overload intensity. The difference was that the client used greater momentum and performed less work (reduced tension) per rep during the set. As a result they actually performed less work. The bottom line is that the HIT system requires specific guidelines that must be understood and practiced in order to achieve maximum strength gains and have direct accountability of strength improvement with each set. Accurate records are essential.

Based on the above example, the following is the correct approach: The client should keep the weight at 100 lbs. for the next workout and try to exceed the time of tension, 70 seconds, to failure. This would show accountable strength gains and will ensure that the client does not cheat by adding more momentum to the set.

Most non-HIT clients are not even aware of their rep speeds and will average 1.5 to 2.5 seconds per rep. Performing reps at that speed will minimize muscle recruitment and limit the client's ability to maximize strength gains through the full range of motion.

We realize that it is not practical to use a stopwatch to time every set. However, we do highly recommend that the client and trainer use a wristwatch and get a rough idea how long each set takes to complete. The client needs to experiment with time under tension because there is a dramatic learning curve that must be experienced if the program is going to be successful.

2 ) Increase Reps - Set a rep range and focus on reaching the high end of the rep range during the set (refer to table A below). In addition, there must be a time under tension range that corresponds with the rep range. For example, a client sets a rep range from 10 to 12 reps which would correspond with a time under tension range between 60 sec. (10 reps x 6 sec.) and 96 sec. (12 reps x 8 sec.). If the client performs 10 reps in 65 seconds the average rep would be 6.5 seconds. The next workout the client is going to try to reach 11 to 12 reps, with the average rep time of 6.5 seconds or greater (72 seconds).

We believe that all clients should be motivated to increase reps during every workout. However, the client must be aware of the "time under tension" variable as they continue to increase reps because eventually they will hit a strength plateau and time of tension will be the most important variable.

Chart A:  Time Under Tension for Rep Ranges

Rep Range	Time Under Tension	Rounded Off
6 - 9	36 to 72 seconds	*40 -75 seconds
9 - 12	54 to 96 seconds	*55 - 100 seconds
12 - 16	72 to 128 seconds	*75 to 130 seconds
16 - 20	96 to 160 seconds	*100 to 160 seconds

* Time under tension rounded off

3) Increase Weight- Once the client has reached the top of the rep range and the top of the time under tension range it is time to increase the weight accordingly. Prior to increasing weight consider the following variables:

1. How many weeks the client has been doing the HIT program
2. Physical size (body type)
3. Previous strength records
4. Targeted muscle group(s)
5. Type of exercise i.e. single vs. double jointed
6. The amount of weight being applied

The average increases should be between 5-10%. Usually 5 % for double-jointed movements and 10% for single-jointed movements is a safe guideline for the majority of clients. Make sure that the increase does not affect the client’s ability to perform perfect reps within the low end of the rep range and time under tension range.

The “triple progressive” overload process is the best way to accurately assess whether there is actual evidence showing direct accountable strength gains. Again, it is worth repeating, timing sets is not easy to do but will help educate the client and trainer on how to perform perfect reps within the time of tension parameters.

NSPA realizes that this information is reinforcing the applications and philosophies that you learned while achieving your NSPA certification. We truly believe that all NSPA certified trainers have a distinct advantage over other trainers in the industry and that makes us very proud.

Written by: NSPA Staff

© June 2003 by the National Strength Professionals Association (NSPA) All rights reserved. Reprint of Article by permission only.