What is Computerized Resistance Equipment?

There are many different forms of strength training which include free weights, selectorized, plate-loaded and computerized resistance equipment. Life Fitness® Circuit is the only true computerized strength training system. It's designed to take advantage of the attributes available only on computerized resistance equipment, and its uniqueness comes from the ability to provide heavier eccentric resistance. Instead of weight plates to remove or load, up to 500 lbs. of resistance is produced by a computer-controlled 1HP DC motor, gears and an electronic cam profile. Life Fitness Circuit consists of 12 units designed to work every major muscle group in the body.

Scientific Support for the Benefits of Computerized Resistance Training

There are three benefits to Life Fitness Circuit that make computerized resistance an ideal form of strength training for those who are new or returning to exercise.

Effective
Computerized resistance training provides a variety of program profiles. For an effective workout, Life Fitness Circuit offers a choice of three training programs:

• Progressive resistance pyramid profile with heavier eccentric resistance (Life Circuit program)
• Heavier eccentric resistance (Regular with heavy negative program)
• Equal concentric/eccentric resistance (Regular resistance program)

Unique to Life Fitness Circuit are the heavier eccentric resistance programs (heavy negative). These programs automatically make the negative resistance (eccentric) 15 percent to 40 percent heavier than the positive (concentric).

• It has been shown that moderate intensity strength training on Life Fitness Circuit, only twice a week, increased muscular strength and improved selected functional activities of daily living in elderly adults.18
• Heavier eccentric loads have been shown to produce greater strength gains compared to traditional strength training. 4,9,14,24,25
• Performing one set on Life Fitness Circuit with heavy negatives repeatedly has been shown to enable the user to achieve faster strength gains than performing three sets of traditional strength training.1,2,10,11
• Many studies have provided evidence supporting the idea that heavier eccentric training can result in quicker strength gains compared to traditional strength training. 5,9,12,13,15,21,23

Safe
The ability for the elderly and deconditioned to safely strength train is a major concern. Research has shown that strength training with Life Fitness Circuit using heavier eccentric loads is a safe method for this population.

• Fleck and Kraemer (1997) explain that eccentric training allows the lifting of a resistance that is equal to or less than a person's 1-repetition max (RM) and then lowering a weight heavier than the 1RM . They also explain that isokinetic machines that are electronically controlled (such as Circuit) increase the safety of a heavier eccentric load so it is easy to lower more weight in a controlled manner.8
• It has been observed that Life Fitness Circuit, offering either greater eccentric loading or equal concentric/eccentric resistance, provided a safe and enjoyable alternative to more conventional strength training methods for the elderly adult.18
• Research showed that Life Fitness Circuit was an effective, safe and comprehensive training program to increase muscular strength.22
• There is a growing body of research showing that the elderly have the capacity to safely strength train and achieve strength gains at similar rates to those of much younger persons. 6,16,18,19,20

Motivating
The technology behind Life Fitness Circuit allows for motivating feedback and results. Users can realize their success with the ability to change weight in 1-lb/1-kg increments. Also, helpful feedback regarding the average weight lifted, current positive and negative weight, average range of motion and number of reps completed are displayed at the end of every set.

• Howley and Franks (1997) explain that the key to motivational feedback is that it must provide helpful and interesting information on an activity.26
• Life Fitness Circuit improved individuals' evaluation of their overall physical fitness and physical acceptance of the shape of their bodies and improved their self-esteem and mood. 2,3

Why is Computerized Resistance Equipment Effective for Elderly and Deconditioned Users?

As detailed in the information above, those who are new and returning to exercise, which include the elderly, deconditioned, beginners and exercise dropouts, can benefit from computerized resistance training. The following additional points support why Life Fitness Circuit is beneficial for this population:

• Johnson (1976), in an article in Medicine and Science in Sports and Exercise, revealed that there are studies indicating eccentric movements are easier to perform than concentric loads.12
• There are quick initial gains in strength when a "beginner" starts a strength training program.17
• A significant increase in strength can be realized within the first three weeks of training.15

Additional Science behind Life Fitness Circuit

Strength training for the elderly and deconditioned is only one application well suited for Life Fitness Circuit. The following research has also shown that Life Fitness Circuit can benefit those in weight management and rehabilitation programs:

• Sedentary females who used Life Fitness Circuit as their strength training component significantly increased strength, replicating studies showing the importance of including strength training in a program for effective weight loss.4
• Studies compared changes in lean body mass. The Life Circuit program produced a trend toward a greater increase in lean body mass and greater reductions in fat. It was indicated that improvements in lean body mass were the result of the eccentric training.1
• Strength training performed on Life Fitness Circuit brought about significant changes in almost all muscle groups for strength and elasticity and resulted in improved muscular balance and rehabilitation from chronic back pain.7

NOTES

1. Ahlquist, L., R. Hinkle, L. Webber, A. Ward & J. Rippe. The effect of four strength training programs on body composition in sedentary men. University of Massachusetts Medical School. Presented at the National Meeting of the Canadian Association of Sports Sciences, 1991.
2. Ahlquist, L., A. Ward, & J. Rippe. The effectiveness of different weight-training protocols on muscle strength and muscle cross-sectional area; body composition and various psychological parameters. Internal Report from the Exercise Physiology and Nutrition Laboratory, University of Massachusetts Medical Center, 1991.
3. Brown, D., Y. Wang, R. Hinkle, L. Webber, L. Ahlquist, E. Puleo, A. Ward & J. Rippe. The effects of four strength training programs on body cathexis, physical estimation and self-esteem. Exercise Physiology and Nutrition Laboratory, University of Massachusetts Medical Center, Medicine and Science in Sports and Exercise, 23:S82, 1991.
4. Castellani, J., A. Ward, B. Marks, D. Kelleher, E. Puleo & J. Rippe. The effects of diet and exercise on strength in moderately overweight women. University of Massachusetts Medical School, Medicine and Science in Sports and Exercise, 23:S142, 1991.
5. Colliander, E. & P. Tesch. Responses to eccentric and concentric resistance training in females and males. Acta Physiologica Scandinavian, 141: 149-156, 1990.
6. Dupler, T. & C. Cortes. Effects of a whole body resistive training regimen in the elderly. Gerontology, 39, 314-319, 1993.
7. Ehrhardt-Schmelzer, S. & S. Keller. Ambulant rehabilitation in patients with chronic back pain; results of a controlled study. ZAT - 1-2/97, p. 12-21, 1997.
8. Fleck, S. & W. Kraemer. Designing Resistance Training Programs, 2nd Edition, Human Kinetics, 1997.
9. Hakkinen, K. & P. Komi. Effect of different combined concentric and eccentric muscle work regimes on maximal strength development. Journal of Human Movement Studies, 7:33-44, 1981.
10. Hinkle, R., L. Webber, L. Ahlquist, A. Ward, D. Kelleher & J. Rippe. The effect of different strength protocols on selected strength measures. University of Massachusetts Medical School, Presented at the National Meeting of the Canadian Association of Sports Sciences, 1991.
11. Hinkle, R., L. Webber, L. Ahlquist, A. Ward, D. Kelleher & J. Rippe. The effect of added eccentric resistance training on selected strength measures. University of Massachusetts Medical School, presented at the Canadian Association of Sports Sciences, 1991.
12. Johnson, B., et al. A comparison of concentric and eccentric muscle training. Medicine and Science in Sports and Exercise, 8: 35-38, 1976.
13. Lacerte, M. et al. Concentric versus combined concentric-eccentric isokinetic training programs: Effect on peak torque of human quadriceps femoris muscle. Archives of Physical Medicine and Rehabilitation, 73: 1059-1062, 1992.
14. MacMillan, M., M. Robinson, M. Gottlich, R. O'Connor and R. Hardouin. The effect of enhanced-eccentric resistance on quadriceps training (Unpublished thesis). Department of Orthopaedics, University of Florida, (1994).
15. Mannheimer, J. A comparison of strength gain between concentric and eccentric contractions. Physical Therapy, 49: 1201-1207, 1968.
16. Meridith, C., & W. Frontera, et al. Body composition in elderly men: Effect of dietary modifications during strength training. Journal of the American Geriatric Society, 40, 155-162, 1992.
17. Moritani, T. Time course of adaptations during strength and power training. Strength and Power Sport, Ed. Kami, P.V.,Oxford: Blackwell Scientific, 1992.
18. Nichols, J., L. Hitzelberger, J. Sherman & P. Patterson. Effects of resistance training on muscular strength and functional abilities of community-dwelling older adults. San Diego State University, Journal of Physical Activity and Aging, Vol. 3, # 3, 251-260, 1995.
19. Rantanen, R., et al. Maximal isometric strength and mobility among 75-year-old men and women. Age and Aging, 23, 132-137, 1994.
20. Roman, W., et al. Adaptations in the elbow flexors of elderly males after heavy resistance training. Journal of Applied Physiology, 74, 750-754, 1993.
21. Seliger, V., et al. Adaptations of trained athletes' energy expenditure to repeated concentric and eccentric muscle actions. International Physiology, 26: 227-234,1968.
2.2 Stauffer, R., J. Schoen, B. Bennett, P. LaChance, J. Lemperle, H. Collier, T. Crowder & J. Borgardus. Physiological effects of a comprehensive circuit training program on middle-aged military men. United States Military Academy, West Point, Presented at ACSM National Meeting, 1992.
23. Tesch, P., A. Thornsson, & E. Colliander. Effects of eccentric and concentric resistance training on skeletal muscle substrates, enzyme activities and capillary supply. Acta Physiologica Scandinavica, 140: 575-580, 1990.
24. Murphy, R.M., T.W. Kaminski & C.V. Wabbersen. Comparison of concentric versus eccentric hamstring strength training using the (trademarked) device. Unpublished data, March 1997.
25. MacMillan, M. Principles and Practice of Eccentric Exercise. Unpublished manuscript, (Department of Orthopaedics—University of Florida), Gainesville Sports Organizing Committee, Inc., April 20, 1996.
26. Howley, E.T. & B.D. Franks. Health and Fitness Instructor's Handbook, Human Kinetics, pg. 119, 1997.