FitBits
April 15, 2006
Exercise ETC’s Review of Exercise Related Research
Compiled by Jeannie Patton, MS, CSCS
Exercise decreases risk of death by as much as 46% among older adults with CAD
A recent statement from the American Heart Association recognized the importance of physical activity for clients with coronary artery disease (CAD). The purpose of this study was to examine the relationship between physical activity and mortality risk in individuals with established CAD. The study also set out to determine whether the relationship between physical activity and mortality is independent of other personal characteristics, and to estimate the risk of mortality associated with changes in physical activity among those with CAD.
Subjects included 1045 older men and women with CAD. The analysis included physical activity levels at baseline and over a nine-year period, while evaluating risk factors associated with CAD.
The study found that the risk of mortality decreased as levels of physical activity increased, finding that the mortality risk was decreased by 10% at 500 calories per week, 19% at 1000 calories per week, 30% at 2000 calories per week, 38% at 3000 calories per week, 43% at 4000 calories per week and 46% at 5000 calories per week. he results also indicated that independent of age, gender, smoking habits, obesity, or type of CAD, the risk of mortality was lower in active participants than inactive participants. The study found that the risk for mortality increased in those who decreased their physical activity and decreased in those who increased their physical activity.
This study highlights the inverse relationship between physical activity and mortality in older men and women with CAD. It is unrealistic for hospitals to provide and monitor physical activity for all CAD patients, so home and gym-based programs could open up a new market for Fitness Professionals. Based on the results of this study the benefits of such non-clinical programming far outweigh the risks.
Janssen, Ian & Jolliffe, Courtney. Influence of physical activity on mortality in elderly with coronary artery disease. Medicine & Science in Sports & Exercise. 2006, 38(3), 418-423.
Push-up variations change muscle activation patterns & spinal loads
The push-up is sometimes used as a torso stabilization exercise. Since some clients complain of back pain while performing push-ups a better understanding of the muscles recruited and the loads on the spine in various push-up positions aids in developing safer and more effective programs. The purpose of this investigation was to measure muscle activation patterns and spinal load for a variety of push-up styles.
Ten healthy college aged men (9) and women (1) served as subjects. The push-up variations included the standard push-up, single arm push-up, uneven hand placement push-up with left-hand forward, uneven hand placement push-up with right hand forward and plyometric (clap) push-up. Other variations included doing push-ups with one hand on a ball and one hand on the floor, each hand on a ball, both hands on one ball, and alternating hands on the ball.
The plyometric (clapping) push-ups resulted in the highest muscle activation as well as the highest spinal loading, while placing the hands on a ball resulted in only modest increases in spinal load. The one arm push-up resulted in the highest spinal compression. The study found that the activation of the right external and internal obliques was higher in the uneven hand placement with the left hand forward and left side activation was highest when the right hand was forward.
It would appear from this study that increases in muscle activation for the torso can be obtained with modest increases in spinal load while performing push-ups with the hands on a ball. Greater muscle activation can be obtained by performing plyometric and one arm push-ups, with the trade off being increased spinal loading: these types of push-ups should be done only by very advanced clients.
Freeman, Stephanie. et al. Quantifying muscle patterns and spine load during various forms of the push-up. Medicine & Science in Sports & Exercise. 2006, 38(3), 570-577.
Perceived barriers affect exercise adherence after physical therapy
Adhering to an exercise program is essential to maintaining the benefits. Fitness Professionals benefit from having a better understanding of what factors enhance or detract from adherence to exercise programs. The purpose of this study was to look at factors affecting adherence for older adults with impaired balance following discharge from physical therapy.
The subjects were 556 older adults (65 years of age) who were discharged from physical therapy from 2000 to 2003. A survey was designed to determine participation in a home exercise program and to identify specific barriers and motivators that were associated with exercise participation following discharge from physical therapy.
Ninety percent of respondents reported receiving a home exercise program upon completion of physical therapy, but over a third (37%) no longer performed it. A change in health status was the primary reason for poor adherence to a home exercise program. Other barriers to exercise included lack of interest, bad weather, depression, weakness, fear of falling, shortness of breath, and low expectations as to the outcome.
The results of this study demonstrate that exercise adherence following discharge from a physical therapy program is poor among older adults. The results also indicate that lack of adherence is related more to perceived barriers rather than lack of motivation. In this study, a change in health status was listed as the number one reason for discontinuing exercise, but perhaps periodic follow up would help to overcome this barrier. When trainers are consulting with a prospective new client after discharge from physical therapy, perhaps a discussion of perceived barriers would be prudent. Fitness Professionals should discuss these perceived barriers with their clients and look for ways to overcome them.
Rebecca, Forka. et al. Exercise adherence following physical therapy intervention in older adults with impaired balance. Journal of Physical Therapy. 2006, 86 (3), 401-410.
Head & eye position affects trunk flexion during squats
The squat is one of the most frequently used exercises for strengthening the major muscles of the trunk and legs. The purpose of this study was to determine if where the client looks -- up, down or straight ahead -- influences the mechanics of the squat.
Ten men experienced in the squat exercise served as subjects. They completed 2 sets of 5 repetitions at 25% of the 1RM under three different conditions: looking up, looking straight ahead and looking down.
The mechanics while looking up and straight ahead were similar for all variables tested, but the downward gaze was shown to increase the amount of hip flexion and trunk flexion.
Based on the results of this investigation, it appears that instructing clients to look straight ahead or slightly up is warranted. This will help the client to avoid the possibility of increased trunk flexion against resistance. This study used individuals who were experienced in the squat exercising at a very low intensity. It would be interesting to see if a greater change in mechanics would occur either with less experienced exercisers or with a heavier resistance. If that were the case, then the head and eye position would become even more important to the safety and effectiveness of the squat.
Donnelly, David. Et al. The effect of the direction of gaze on the kinematics of the squat exercise. National Strength & Conditioning Journal. 2006, 20(1), 145-150
Del.Icio.Us Tags: FitBits, Exercise, Fitness, Push ups, Squats, CAD, Heart disease, Physical therapy, Truck stability
Technorati Tags: FitBits, Exercise, Fitness, Push ups, Squats, CAD, Heart disease, Physical therapy, Truck stability
No comments:
Post a Comment