Guest guest Posted May 16, 2003 Report Share Posted May 16, 2003 Hi Ulf! If you look into any exercise physiology text you will find numerous studies that support isometric exercise for strength gains. Most of the studies indicate that the strength gains are generally angle specific. Best wishes! Dan Wathen, Youngstown (OH) State University In Supertraining , " Ulf Karlsson " <ulf.karlsson@t...> wrote: > I've tried this topic twice before. > > " Are isometrics effective? " > > I didn't get a real answers, because - I suppose - people compared > isometrics to lifting weights, which of course is more effective. > > That's not really what I'm interested in. What I would want to know > is if isometrics have any effect at all and how they should be used. Some say > everyday ,a 10 sec. contraction per muscle group, some say 5 secs a > week, some say 20 5-sec contractions per day per muscle group. Some > say there can only be increases in strength at the angle you train > your muscle, some say the whole range is effected, some say the > largest strength gains are made in the angle in which the muscle is > trained BUT the strength is increase throughout the ROM but to a > lesser extent. > > The problem today is that there are people who work out a lot and are > completely crazy about staying fit and being muscular. Then > there are those who just sit at home in front of the TV and drink > beer and cola and eat chips and NEVER move, getting fat and slobby > and dying from heart attacks at the age of 45. There's almost > nothing in between today. > > If we look at the issue from a health care cost perspective, society > would benefit a lot from getting these people living more healthy. > The problem is that getting super fit takes a lot of time and people > have unrealistic expectations. Getting people off their butts with > realistic expectations would be a great thing. > > But a lot of people don't want to go to the gym. As far as strength > training goes, keeping muscles, joints and bones in shape, if a 10 > minute a day isometric programme has positive effects compared to > doing nothing, that'd be a great way of getting people moving in a > healthier direction especially if results are visible. When I started > working out (and I've stopped and started and stopped and started and > stopped since then) I started with push-ups. The only reason I > started going to the gym was because I could see and feel the > positive results of doing 150 push-ups a day. > > I may be blathering, but I hope you see my point. > > So, how does isometrics REALLY work, what are there benefits, what > kind of results can you expect and what kind of programme (days a > week/number of contractions/ length of contractions) would you need > to see results? > > Needless to say, I don't believe the Pete Sisco nonsense. I'm looking > for some REALISTIC answers. > > Thanks > > Ulf Karlsson > Debrecen, Hungary Quote Link to comment Share on other sites More sharing options...
Guest guest Posted May 16, 2003 Report Share Posted May 16, 2003 Hi Ulf! If you look into any exercise physiology text you will find numerous studies that support isometric exercise for strength gains. Most of the studies indicate that the strength gains are generally angle specific. Best wishes! Dan Wathen, Youngstown (OH) State University In Supertraining , " Ulf Karlsson " <ulf.karlsson@t...> wrote: > I've tried this topic twice before. > > " Are isometrics effective? " > > I didn't get a real answers, because - I suppose - people compared > isometrics to lifting weights, which of course is more effective. > > That's not really what I'm interested in. What I would want to know > is if isometrics have any effect at all and how they should be used. Some say > everyday ,a 10 sec. contraction per muscle group, some say 5 secs a > week, some say 20 5-sec contractions per day per muscle group. Some > say there can only be increases in strength at the angle you train > your muscle, some say the whole range is effected, some say the > largest strength gains are made in the angle in which the muscle is > trained BUT the strength is increase throughout the ROM but to a > lesser extent. > > The problem today is that there are people who work out a lot and are > completely crazy about staying fit and being muscular. Then > there are those who just sit at home in front of the TV and drink > beer and cola and eat chips and NEVER move, getting fat and slobby > and dying from heart attacks at the age of 45. There's almost > nothing in between today. > > If we look at the issue from a health care cost perspective, society > would benefit a lot from getting these people living more healthy. > The problem is that getting super fit takes a lot of time and people > have unrealistic expectations. Getting people off their butts with > realistic expectations would be a great thing. > > But a lot of people don't want to go to the gym. As far as strength > training goes, keeping muscles, joints and bones in shape, if a 10 > minute a day isometric programme has positive effects compared to > doing nothing, that'd be a great way of getting people moving in a > healthier direction especially if results are visible. When I started > working out (and I've stopped and started and stopped and started and > stopped since then) I started with push-ups. The only reason I > started going to the gym was because I could see and feel the > positive results of doing 150 push-ups a day. > > I may be blathering, but I hope you see my point. > > So, how does isometrics REALLY work, what are there benefits, what > kind of results can you expect and what kind of programme (days a > week/number of contractions/ length of contractions) would you need > to see results? > > Needless to say, I don't believe the Pete Sisco nonsense. I'm looking > for some REALISTIC answers. > > Thanks > > Ulf Karlsson > Debrecen, Hungary Quote Link to comment Share on other sites More sharing options...
Guest guest Posted May 19, 2003 Report Share Posted May 19, 2003 Take a look at http://www.isokinetics.net/basics/exercises.htm What this says is that isometric excecise is COMPLELETY USELESS and at the same time DANGEROUS. Ulf Karlsson Debrecen, Hungary > > I've tried this topic twice before. > > > > " Are isometrics effective? " > > > > I didn't get a real answers, because - I suppose - people compared > > isometrics to lifting weights, which of course is more effective. > > > > That's not really what I'm interested in. What I would want to know > > is if isometrics have any effect at all and how they should be used. > Some say > > everyday ,a 10 sec. contraction per muscle group, some say 5 secs a > > week, some say 20 5-sec contractions per day per muscle group. Some > > say there can only be increases in strength at the angle you train > > your muscle, some say the whole range is effected, some say the > > largest strength gains are made in the angle in which the muscle is > > trained BUT the strength is increase throughout the ROM but to a > > lesser extent. > > > > The problem today is that there are people who work out a lot and > are > > completely crazy about staying fit and being muscular. Then > > there are those who just sit at home in front of the TV and drink > > beer and cola and eat chips and NEVER move, getting fat and slobby > > and dying from heart attacks at the age of 45. There's almost > > nothing in between today. > > > > If we look at the issue from a health care cost perspective, society > > would benefit a lot from getting these people living more healthy. > > The problem is that getting super fit takes a lot of time and people > > have unrealistic expectations. Getting people off their butts with > > realistic expectations would be a great thing. > > > > But a lot of people don't want to go to the gym. As far as strength > > training goes, keeping muscles, joints and bones in shape, if a 10 > > minute a day isometric programme has positive effects compared to > > doing nothing, that'd be a great way of getting people moving in a > > healthier direction especially if results are visible. When I > started > > working out (and I've stopped and started and stopped and started > and > > stopped since then) I started with push-ups. The only reason I > > started going to the gym was because I could see and feel the > > positive results of doing 150 push-ups a day. > > > > I may be blathering, but I hope you see my point. > > > > So, how does isometrics REALLY work, what are there benefits, what > > kind of results can you expect and what kind of programme (days a > > week/number of contractions/ length of contractions) would you need > > to see results? > > > > Needless to say, I don't believe the Pete Sisco nonsense. I'm > looking > > for some REALISTIC answers. > > > > Thanks > > > > Ulf Karlsson > > Debrecen, Hungary Quote Link to comment Share on other sites More sharing options...
Guest guest Posted May 21, 2003 Report Share Posted May 21, 2003 No where in the article does it state that isometric exercise is " COMPLETELY USELESS " and the article goes on to qualify the word " DANGEROUS " to a segment of the population. It further asserts that all isometric exercises are performed at two thirds to maximum load. A once over of this article reveals a few flaws not the least of which is lack of full index of references. I have included my comments in [brackets]. <<<<<<<<<< http://www.isokinetics.net/basics/exercises.htm#isotonic Isometric Exercise The term isometric has been abused over a great period of time. [unqualified opinion] At one point, the term tonic contraction was used interchangeably with isometric contraction. This trend seems to be decreasing. Isometric contraction and isometric exercise are again two interchangeable terms. To elaborate on this it seems people describe an isometric contraction as performing isometric exercise. Hislop and Perrine (1967) described isometric exercise as muscular contractions against a load which is fixed or immovable or is simply too much to overcome. Two German physiologists (Muller and Hettinger, 1954) performed a study which claimed that one six second isometric contraction at two- thirds maximum performed once each day for five days was sufficient for 5% strength gains per week. This received a disproportionate amount of publicity from which it would appear that the medical community has never recovered. [unqualified opinion] Although it has been shown that strength gains are possible from isometric contraction these strength gains are very minimal and almost all studies since have shown that the gains in pure muscular strength are only at the specific angle at which the exercise is performed. [source?] Hence, to make isometric exercise effective at increasing functional strength it must be repeated at many different joint angles. Isometric improvements have also been shown to be rate specific (sey, Harman and 1995), this means that isometric strength gains can be best utilized only at particular speeds. These improvements are seen mostly in slower movements which are not functional [Across full range of motion?] and of little use to people wishing to return to any kind of physical activity. [Overgeneralization] Isometric exercise does not, contrary to popular opinion, increase muscular endurance or functional capacity in real world situations. [unqualified opinion, Overgeneralization] The extreme effort involved with isometric exercises causes considerable internal pressure both within the muscles themselves and in the abdominal and thoracic cavities. Isometric exercise can increase blood pressure and heart rate to levels that would be dangerous for anyone with undiagnosed cardiac problems (Nagle, Seals and Hanson 1988, White and Carrington 1993 and Baum et al. 1995), whilst also increasing intra abdominal pressure to dangerously high levels ( and Lind 1987). For those in good health this is not problematic however, for those who have suffered muscular or tendonus injuries, the consequences can be dire. Isometric exercises are, however, extremely good for strengthening muscle groups around an injured joint as the joint surfaces actually distract from one another during isometric contraction. However, following isometric exercise there is a decrease of muscle power by up to 60-70% (Tidas and Shoemaker 1995), this can last for up to 96hrs (4 days). During this time the associated joints are exposed to much higher than normal impact and sheer forces as they have lost one of their most vital protective mechanisms. This could lead to discomfort as demonstrated by Melchionda et al. (1984) which is not experienced with isokinetic concentric contractions (Dvir 1995). In reality electrical stimulation of a muscle is more effective at increasing muscular strength than isometric exercise as has been shown by Draper and Ballard (1991). Isotonic Exercise Isotonic literally means equal tension. In exercise science isotonic contraction is a contraction in which the tension remains constant as the muscle shortens or lengthens. Although `isotonic' is the term used most frequently to describe fixed resistance variable speed exercise, `isoinertial' is a more accurate description of this type of movement (Abernethy et al. 1995). I will continue to use isotonic throughout. In reality it takes a very complicated piece of equipment, like an active dynamometer, to create pure isotonic exercise. People generally think of isotonic exercise as that seen in the gymnasium. The simplest example of this is where a dumbbell is lifted from the ground and used to perform an exercise. The tension generated by the dumbbell is now the constant, or in other words if you pick up a 2 kilo dumbbell it weighs 2 kilos whatever you do with it. The elaborate cam systems seen on most modern weight training equipment allow for a more isotonic movement to be performed. The key to isotonic exercise is that although the weight is constant the speed of movement associated with the exercise is variable. Think again of the dumbbell curl. The dumbbell always weighs 2 kilos but you can decide how quickly to move it.# Although the reliability of isotonic exercise is generally good, controlling the inertial forces that develop with different lifting techniques make it inappropriate for the study of musculoskeletal performance in humans (Sapega 1990). This method of testing should be limited to active dynamometers. Even then isotonic movement should only be used for the assessment of speed production at a given resistance. Exercise programs have been proven to be most effective when the movements performed match those experienced most frequently by the person in question (sey, Harman and 1995). For humans the closest form of exercise to normal movement is isotonic. So it would not be surprising to find that isotonic exercise increases muscle strength at double the speed of isometric exercise in the untrained population according to Connelly and Vandervoort (1995). [unqualified opinion, Overgeneralization, Unsupported conclusion] Isokinetic Exercise This form of exercise is in contrast to the other forms in that it permits maximum muscle contraction throughout the full range of joint movement. You will often seen it referred to as `accommodating resistance exercise' (a term first introduced by Hislop and Perrine, 1967). The resistance is now variable in proportion to the change in muscular capability at every point in the range of motion. The variation is controlled so that at all times it equals the product of the muscular strength. There are two major types of machine available to offer isokinetic exercise. Type 1 - an active dynamometer (the most familiar to clinicians). In this type of exercise the speed is controlled whilst resistance is variable according to the amount of force throughout the range of movement. No matter how much force the individual applies the speed does not change. Thus the motion of the body segment is kept at a predetermined velocity. Type 2 - utilizes a change in the moment arm of the selected resistance to coincide with the change in moment arm of the muscle effort and the change in tension due to muscle length change. The resistance thus accommodates the continuous changes in muscle force which occur throughout the range of movement. The changes in the resistance arm on the machine are determined and pre-set to coincide with the average strength curves for various joint actions (obviously this involves a different machine for each movement). >>>>>>>>> Dennis Pasadena, CA USA Quote Link to comment Share on other sites More sharing options...
Guest guest Posted May 21, 2003 Report Share Posted May 21, 2003 No where in the article does it state that isometric exercise is " COMPLETELY USELESS " and the article goes on to qualify the word " DANGEROUS " to a segment of the population. It further asserts that all isometric exercises are performed at two thirds to maximum load. A once over of this article reveals a few flaws not the least of which is lack of full index of references. I have included my comments in [brackets]. <<<<<<<<<< http://www.isokinetics.net/basics/exercises.htm#isotonic Isometric Exercise The term isometric has been abused over a great period of time. [unqualified opinion] At one point, the term tonic contraction was used interchangeably with isometric contraction. This trend seems to be decreasing. Isometric contraction and isometric exercise are again two interchangeable terms. To elaborate on this it seems people describe an isometric contraction as performing isometric exercise. Hislop and Perrine (1967) described isometric exercise as muscular contractions against a load which is fixed or immovable or is simply too much to overcome. Two German physiologists (Muller and Hettinger, 1954) performed a study which claimed that one six second isometric contraction at two- thirds maximum performed once each day for five days was sufficient for 5% strength gains per week. This received a disproportionate amount of publicity from which it would appear that the medical community has never recovered. [unqualified opinion] Although it has been shown that strength gains are possible from isometric contraction these strength gains are very minimal and almost all studies since have shown that the gains in pure muscular strength are only at the specific angle at which the exercise is performed. [source?] Hence, to make isometric exercise effective at increasing functional strength it must be repeated at many different joint angles. Isometric improvements have also been shown to be rate specific (sey, Harman and 1995), this means that isometric strength gains can be best utilized only at particular speeds. These improvements are seen mostly in slower movements which are not functional [Across full range of motion?] and of little use to people wishing to return to any kind of physical activity. [Overgeneralization] Isometric exercise does not, contrary to popular opinion, increase muscular endurance or functional capacity in real world situations. [unqualified opinion, Overgeneralization] The extreme effort involved with isometric exercises causes considerable internal pressure both within the muscles themselves and in the abdominal and thoracic cavities. Isometric exercise can increase blood pressure and heart rate to levels that would be dangerous for anyone with undiagnosed cardiac problems (Nagle, Seals and Hanson 1988, White and Carrington 1993 and Baum et al. 1995), whilst also increasing intra abdominal pressure to dangerously high levels ( and Lind 1987). For those in good health this is not problematic however, for those who have suffered muscular or tendonus injuries, the consequences can be dire. Isometric exercises are, however, extremely good for strengthening muscle groups around an injured joint as the joint surfaces actually distract from one another during isometric contraction. However, following isometric exercise there is a decrease of muscle power by up to 60-70% (Tidas and Shoemaker 1995), this can last for up to 96hrs (4 days). During this time the associated joints are exposed to much higher than normal impact and sheer forces as they have lost one of their most vital protective mechanisms. This could lead to discomfort as demonstrated by Melchionda et al. (1984) which is not experienced with isokinetic concentric contractions (Dvir 1995). In reality electrical stimulation of a muscle is more effective at increasing muscular strength than isometric exercise as has been shown by Draper and Ballard (1991). Isotonic Exercise Isotonic literally means equal tension. In exercise science isotonic contraction is a contraction in which the tension remains constant as the muscle shortens or lengthens. Although `isotonic' is the term used most frequently to describe fixed resistance variable speed exercise, `isoinertial' is a more accurate description of this type of movement (Abernethy et al. 1995). I will continue to use isotonic throughout. In reality it takes a very complicated piece of equipment, like an active dynamometer, to create pure isotonic exercise. People generally think of isotonic exercise as that seen in the gymnasium. The simplest example of this is where a dumbbell is lifted from the ground and used to perform an exercise. The tension generated by the dumbbell is now the constant, or in other words if you pick up a 2 kilo dumbbell it weighs 2 kilos whatever you do with it. The elaborate cam systems seen on most modern weight training equipment allow for a more isotonic movement to be performed. The key to isotonic exercise is that although the weight is constant the speed of movement associated with the exercise is variable. Think again of the dumbbell curl. The dumbbell always weighs 2 kilos but you can decide how quickly to move it.# Although the reliability of isotonic exercise is generally good, controlling the inertial forces that develop with different lifting techniques make it inappropriate for the study of musculoskeletal performance in humans (Sapega 1990). This method of testing should be limited to active dynamometers. Even then isotonic movement should only be used for the assessment of speed production at a given resistance. Exercise programs have been proven to be most effective when the movements performed match those experienced most frequently by the person in question (sey, Harman and 1995). For humans the closest form of exercise to normal movement is isotonic. So it would not be surprising to find that isotonic exercise increases muscle strength at double the speed of isometric exercise in the untrained population according to Connelly and Vandervoort (1995). [unqualified opinion, Overgeneralization, Unsupported conclusion] Isokinetic Exercise This form of exercise is in contrast to the other forms in that it permits maximum muscle contraction throughout the full range of joint movement. You will often seen it referred to as `accommodating resistance exercise' (a term first introduced by Hislop and Perrine, 1967). The resistance is now variable in proportion to the change in muscular capability at every point in the range of motion. The variation is controlled so that at all times it equals the product of the muscular strength. There are two major types of machine available to offer isokinetic exercise. Type 1 - an active dynamometer (the most familiar to clinicians). In this type of exercise the speed is controlled whilst resistance is variable according to the amount of force throughout the range of movement. No matter how much force the individual applies the speed does not change. Thus the motion of the body segment is kept at a predetermined velocity. Type 2 - utilizes a change in the moment arm of the selected resistance to coincide with the change in moment arm of the muscle effort and the change in tension due to muscle length change. The resistance thus accommodates the continuous changes in muscle force which occur throughout the range of movement. The changes in the resistance arm on the machine are determined and pre-set to coincide with the average strength curves for various joint actions (obviously this involves a different machine for each movement). >>>>>>>>> Dennis Pasadena, CA USA Quote Link to comment Share on other sites More sharing options...
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