BOTTOM LINE: Running at your own pace for just a few minutes per day may extend your lifespan.
Most people know a healthy lifestyle of good nutrition and regular exercise reduces mortality. Now new research supports this finding in the case of running. A recent study published in the Journal of the American College of Cardiology has found that running for just five to ten minutes may extend your life by three years. The fascinating aspect of this 15-year study was that the speed, distance, frequency, and duration of running was not as important as running itself. In other words, you can reap the benefits of living longer by running slowly for a few minutes at a time. It's important to keep in mind that this research did NOT prove causation that running increases lifespan but rather that there seems to be a correlation between running and living longer. The research had found a 30 percent lower risk of death among runners compared to non-runners. Those who are more avid runners tend to accrue the most benefit of living longer. Obviously, the health benefits from running such as improved heart and lung function help explain why runners tend to live longer than non-runners.
BOTTOM LINE: Running at your own pace for just a few minutes per day may extend your lifespan.
Fat is a tissue within the body which tends to be predominantly burned during periods of rest as well as during low-intensity cardio (i.e., 65% HRR) . But just because more calories from fat are burned during low-intensity cardio does not mean this is the best way to burn bodyfat. In fact, it takes much longer to burn an equivalent amount of fat performing low-intensity cardio versus high-intensity cardio. In other words, you can burn more calories from fat in less time by performing high-intensity cardio (i.e., 85% HRR) because you burn more calories in general compared to low-intensity cardio. For example, if you perform 30 minutes of low-intensity cardio, you may burn up to 200 calories of which 100 calories came from fat. On the other hand, if you perform the same duration (30 minutes) at twice the intensity, you may burn up to 400 calories of which 160 calories came from fat. Thus, you will burn more fat when performing high-intensity cardio by virtue of burning more calories in general. In addition, high-intensity cardio tends to elevate the metabolic rate for a period after the exercise more so than low-intensity cardio. This means high-intensity cardio promotes an "afterburner" effect in which even more calories are burned from fat several hours post-exercise. If you perform twice the duration of low-intensity cardio in the example above (60 minutes), you will burn more fat calories than high-intensity cardio but the overall calories burned will be about the same compared to high-intensity cardio performed at half the duration (30 minutes). In other words, low-intensity cardio is not an efficient means of burning bodyfat compared to high-intensity cardio.
BOTTOM LINE: High-intensity cardio is the most efficient way to burn bodyfat. Interval training is another means to efficiently burn more fat calories as well.
Prepare yourself for the top foods that contribute to belly fat in our society. Most Americans love these foods but unless these foods are eaten occasionally (i.e., at most once per week), you can kiss your goal of acquiring six-pack abs goodbye.
Here are the worst foods you should resist the urge to eat due to high-calorie content :
Here are better foods you should eat to reduce belly fat:
Also, be sure to exercise to lose bodyfat--emphasize compound, full-body weight training movements and cardio intervals. Bear in mind that spot-reduction is a myth.
A recent study published in Clinical Rehabilitation found that walking can be just as beneficial as strength training in lessening chronic lower back pain. You're never too old or out of shape to walk. Strive to walk for up to 40 minutes to obtain the most benefit of reducing back pain. Gentle yoga may also lessen lower back pain. Be sure to seek the guidance of an experience instructor.
Sprinting is guaranteed to burn bodyfat, particularly when performed in the morning before eating breakfast. Sprinting is a superb fat-fighting exercise because it involves short bursts of energy, significantly elevating your metabolic rate. The recommended manner in which to perform sprints is in an interval fashion with progressive intensity levels as your body adapts to the training stimulus. Never jump right in to full-on sprints at maximum intensity (e.g., 100% HRR) until your body has adapted. Best to gradually work up to intensity levels which are at submaximal intensities (e.g., 70 to 90% HRR). Be sure to take it slow and work up to increased intensity levels. Besides intensity level, consider the frequency and duration of your sprints. Better to be conservative on these aspects as well. Twice per week at 30 to 45 minutes is adequate to achieve fat-burning results when sprinting. Only sprint on a cushioned surface such as a running track, artificial turf or grass--avoid pavement to spare your hip and knee joints. Lastly, be sure to wear a good pair of running shoes with a flat sole--minimus New Balance shoes are ideal.
What's a great low-impact cardio exercise that puts less stress on your back, hips, knees and ankles?
Walking is the best land-based exercise that spares your joints from injury and pain. The best thing about walking is anybody can do it no matter the skill level. To make walking a great cardiovascular workout in which you'll burn more calories, be sure to walk at a quick pace. You should be walking as fast as you can short of running (i.e., about four miles per hour). In order to effectively do this, you should pump your arms with the elbows in a bent position (i.e., about a 90-degree angle) while swiveling your hips. This allows your body to move forward more quickly and efficiently due to less side-to-side movement. Pumping or swinging your arms at the shoulders in sync with your feet also enhances forward momentum. Be sure to maintain good posture by keeping your chin up, head level, shoulders relaxed, and back straight. Speed walking is one of the safest and easiest exercises you can do to get in a superb cardiorespiratory workout. Start with a 20-minute walk three to five times per week and gradually increase the pace on a weekly basis. You can make your walks more interesting by wearing a weighted backpack and/or going on hill walks. You can also try interval walks in which you alternate your pace from fast to a slower speed.
BOTTOM LINE: Research has indicated that those who tend to walk faster have lower mortality rates but any kind of walking is better than no walking at all. Just be sure to put on a pair of comfortable, flexible shoes and get out there and walk!
Besides affecting your cardiovascular and pulmonary system, performing cardio exercise regularly affects your body composition, hormonal system, skeletal system, metabolic system, cognitive sytem, immune system, athletic performance, and quality of life.
Power walking involves walking at a brisk pace (e.g., 5 miles per hour). This is a superb exercise for those who want to spare their joints (e.g., back, hips, knees, ankles) from high impact and for those who may have orthopedic issues (e.g., arthritic knees). Power walking can provide cardiovascular benefits comparable to running. It entails having one foot touching the ground at all times with the front leg being relatively straight when it contacts the ground. To get the most out of power walking, you should strive to move as quickly as possible in order to burn more calories and become more fit. Here are some tips to better your technique and to help move at a faster pace:
Contrary to a popularly-held belief, cardio generally does not burn more calories than weight training. I say "generally" because so many confounding factors play a part (i.e., duration, intensity, interval training, etc.). Taking into account the same duration and comparable intensity levels (i.e., METS), weight training burns more calories than cardio. The primary reason for this is twofold:
BOTTOM LINE: If you want to burn more calories in order to lean out or lose body weight, be sure to lift the weights!
Note: Steady-state cardio generally does not cause EPOC although interval and HIIT cardio sessions do cause EPOC.
The answer is simple although the people who use these machines probably are not aware of why they use them. The reason people tend to opt for the elliptical machine rather than most other machines is because it's very easy on the joints and does not require much resistance to move the body. In other words, the elliptical machine is the easiest cardio activity to do. Because it is easy, people naturally want to use it rather than to try a machine that might take them out of their comfort zone.
The elliptical machine can be very useful for older adults or those with arthritis, but for most people it's not a very efficient tool to burn calories. The winner in the caloric expenditure department goes to the treadmill, followed by (from highest to lowest caloric expenditure) the stairstepper (stepmill), the rowing machine, the upright bike, and finally the recombinant bike.
The reality is that, in general, the elliptical machine does not elevate the heart rate nor does it burn bodyfat adequately. This is due to the fact that movement on these machines relies primarily on momentum rather than resistance. Momentum is simply the product of a body's mass and its velocity. Just as in weight training, if you move the joints quickly (increasing velocity), momentum increases while resistance decreases. The net result is essentially less real work being done since less force (resistance) is exerted. Now you know why people like to move quickly on the elliptical machines: it makes the exercise easier!
No matter which machine you choose, be sure not to lean most of your bodyweight on the hand rails for support. These railings are designed for your balance, not for support. By leaning predominantly on these railings, you'll reduce your caloric expenditure because your lower body will not be working as hard as it should. Straighten your posture by pulling your shoulders back and looking straight ahead. Rest your hands lightly on the rails to get an optimum workout. If you still cannot resist leaning heavily on the rails, you need to reduce the intensity on the machine--you're pushing way too hard. On the other hand, if you can read a book or comfortably breathe through your nose while doing cardio, your intensity level is way too low. Step up the intensity!
Bottom line: if you want to burn serious calories, you have to work hard to do it--sorry, working out on the elliptical machine does not qualify, in most cases, as hard work. Get out of your comfort zone and hit the treadmill, stairstepper or rower instead.
Even though the distance is the same, you will actually burn more calories while running as this exercise is much more intense than walking. Intensity means a higher exercise heart rate, greater muscular movement, and more energy to move your body faster. Also, consider that both feet will be off the ground simultaneously when running in order to maintain a long stride length whereas walking entails one foot on the ground at any one time. The difference in calories between running versus walking the same distance depends on many factors (e.g., body weight, speed, etc.), but the amount could be about 30 or more calories per mile.
Bottom line: Running burns more calories in less time but walking is less traumatic on the joints. Therefore, if you prefer to walk rather than run be sure to walk longer distances or at a faster pace in order to burn higher calories comparable to running.
Is HIIT training just a new fad that's overly hyped by the media with little substantiation for its effectiveness as a means to lose bodyweight?
More and more research lends credence that High Intensity Interval Training (HIIT) is a great way to lose body weight or bodyfat. No longer is the standard protocol of performing low-intensity (e.g., 50 to 65% HRR) cardio exercise recommended as the only way nor the best way to burn bodyfat or lose body weight. Low-intensity cardio is good and can be effective, provided you exercise for relatively long-duration periods (e.g., 45 minutes per session). Nowadays, who has the time for that! Enter HIIT training.
HIIT should not be confused with interval training. The distinction is that HIIT involves extremely-high intensity levels (e.g., 85 to 100% HRR) for very short periods (e.g., 10 to 30 seconds) coupled with low-moderate intensity levels (e.g., 50-65% HRR) whereas interval training usually involves moderately-high intense levels (e.g., 65 to 85% HRR) for relatively longer durations (e.g., 30 seconds to 3 minutes) coupled with low-moderate intensity levels (e.g., 50-65% HRR).
Here are the benefits to performing HIIT:
HIIT training should be performed infrequently due to its high-intensity characteristic. Infrequently means no more than two to three times per week. Performing HIIT any more than three times per week increases the risk of overtraining of which symptoms may include muscle catabolism (read: muscle burning). Generally, HIIT training is a relatively advanced technique due to its high-intensity range and increased risk of injury. When you do HIIT, be sure to do it sparingly. You can perform HIIT while running, cycling, swimming, or stair climbing.
No matter which cardio training you choose to do, the bottom line is that you should burn several hundred calories per session. The best part is that even after you're done exercising, the "afterburner" effect will occur. That is, your metabolic rate will be stimulated to continue to burn much more calories than a sedentary person while resting. How great is that?!! So don't neglect your cardio!
Metabolism is the total of all the chemical and physical processes by which the body builds and maintains itself and by which it breaks down its substances for the production of energy. About 70% of the calories your body burns is used for basic vital processes (e.g., breathing, digestion, muscle anabolism, fat storage, and blood circulation). The remaining 30% may be attributed to physical activity (e.g., walking, cycling, weight training, etc.). Metabolism involves two distinct processes: anabolic reactions, which involve the building of cellular structures and energy storage; and catabolic reactions, which involve the breakdown of molecules for energy.
Metabolic rate, not to be confused with metabolism, is the rate at which your body burns calories or the speed of your metabolism. Both metabolism and metabolic rate are affected by many factors such as age, gender, lifestyle, and hormonal levels. The thyroid gland produces hormones which regulate how fast or how slow your body burns calories and for such things as when your body uses energy to build muscle tissue from protein or stores energy as fat.
The most obvious modifiable factor for affecting your metabolic rate is lifestyle (e.g., physical activity and diet). Exercise, including weight training and cardio, will elevate the body's basal metabolic rate (BMR), which is essentially a baseline metabolic level, even during rest. Weight training, in particular, elevates one's metabolic rate because it increases muscle mass and muscle is a very metabolically-active tissue within the body. As the body ages, muscle mass slowly decreases and as a result, so does metabolic rate. A double whammy is the gain in bodyfat along with the loss of muscle mass, compounding the problem. Interval training (e.g., high-intensity interval training known as HIIT) is a very effective technique used to stimulate positive changes in one's BMR.
Nutrition also plays a part in terms of affecting metabolic rate. Not eating enough food (less than 1200 kcals daily) slows down metabolic rate because the body "thinks" it's starving. Going too long between meals (e.g., more than three hours) will slow down metabolic rate. On the other hand, a relatively high-protein diet will boost metabolic rate because protein is a macronutrient which the body must work harder and therefore expend more calories to digest. Caffeine and some spicy foods (e.g., hot peppers) can boost metabolic rate due to their stimulant qualities.
VO2 is used to designate the volume of oxygen within the blood that is consumed by the body's tissues. Specifically, it is often measured as the volume of oxygen (in milliliters) per kilogram bodyweight per minute. It is an indication of a person's aerobic fitness capacity when engaged in an endurance-type exercise (e.g., jogging, biking, swimming). VO2 escalates as the intensity of exercise increases up to a certain threshold called VO2-max. The magnitude of VO2-max is largely dependent on the cardiovascular health and age of the individual. It is favorable to have a high VO2 for a particular exercise with minimal bodily fatigue--this is indicative that the heart is functioning efficiently. A good personal trainer should ascertain his or her client's VO2-max (either directly by performing a graded exercise test or indirectly by assessing heart rate response to at least two exercise intensity levels) in order to prescribe an appropriate intensity level of cardiorespiratory exercise.
Walking, biking, rowing, and swimming are at the top of the list. All are superb exercises because they are considered low-impact exercises and are therefore easy on the joints. Swimming is ideal for those who are overweight, obese, and/or have osteoarthritis. Swimming is also an excellent exercise for pregnant women. Plus, it's never too late to start! Here are just some of the benefits of swimming:
Myths abound and are prevalent in our society because people like to believe in easy, quick fixes for losing weight and gaining muscle mass. As a result, there is a plethora of products preying on naive consumers in order to make money. The media is mostly to blame since this is how most people obtain information or misinformation in this case.
Many magazine and website editors continually encourage the publication of articles which lack much in the way of factual information and peddle it as new or novel approaches to training or supplementation. The reality is the information provided is simply a retread of what has already been said countless numbers of times, only written in a different way to make the article seem interesting.
But let's not direct all our blame onto the media. Ignorant consumers who "believe" the newest training routine (e.g., the Insanity Workout, P90X, etc.) is the way to achieve the perfect physique are only deluding themselves and actually encourage unscrupulous salespersons to take advantage of the opportunity to rip us off. There is nothing magical about these new trends in exercise routines. If you see it in a late night infomercial, be very wary and view it with a healthy sense of skepticism. Once again, the name of the game is to separate you from your pocketbook.
There is no magic bullet for losing weight or gaining muscle since each individual's body responds uniquely to training stimuli. The key is to utilize the technique of trial and error in discovering which exercises, sets, reps, rest periods, workout splits, etc. work best for you and you alone. Just because the big guy in the gym has built a physique worthy of admiration does not mean he knows exactly what works for you to get big. He may have spent most of his life building his body to what it is today through many years of dedicated and persistent training. Again, everyone responds differently to exercises, nutrition and supplements. Supplement and equipment salespersons' main objective is to sale their product no matter if there is a lack of scientific or biomechanical evidence to back up the product.
Here are some of the common myths regarding exercise, nutrition and supplementation:
Wrong! Cellulite is caused by fatty deposits and fibrous tissue within the subcutaneous layer of the skin. Remember the concept of spot reduction being a worthless way to tone certain muscle groups? The same concept applies here as well. You cannot tone any muscle and expect cellulite to magically go away. The body just does not work that way. Although there is some evidence within the scientific literature indicating that the dimpling caused by cellulite can be temporarily reduced or smoothed out by daily deep tissue massage.
Low-intensity cardio can be effective in burning bodyfat if performed for long durations (e.g, more than 30 minutes), but interval training can be just as effective in burning an equivalent or more bodyfat in less time. The key is the amount of total amount of calories burned during the exercise--that is all that matters as far as the body is concerned. Nutrition is also a big factor in that the body can more efficiently burn bodyfat when there are carbs available. In other words, fat burning occurs more readily when in the presence of carbs. So performing cardio while on a low-carb diet is not the best way to burn bodyfat.
The optimal exercise prescription is one that recommends the combination of cardio and weight training for losing bodyweight. The increase in metabolism caused by muscle stimulation and increased lean body mass causes more calories to be expended, which in turn increases weight loss.
Don't mistake losing bodyweight with losing bodyfat! They are two completely different animals. But more to the point, the bodyweight lost is merely water weight and fluctuates throughout the day. This is why checking your bodyweight before and immediately after working out is only useful for determining how much water you lost and therefore how much you should drink to rehydrate your body. Actually believing you lost poundage from fat after working out is wishful thinking to put it mildly. Incidently, any weight lost by wearing a rubber suit or a sweat shirt while exercising will be mostly water weight, not bodyfat. As soon as you replenish your body with fluids (or food for that matter), those pounds you lost in the gym will return almost as fast as they left. Of course sweating is indicative of a strenuous workout session and can ultimately lead to weight loss.
I think by now you know this idea is preposterous. The phenomenon of "spot reduction" has absolutely no supportive evidence.
Let's get this straight: Muscle tissue is not the same as fat tissue--they are completely distinct body tissues and therefore it is an impossibility for muscle to turn into fat. But having said this, it is true that muscles will lose size and shape from lack of regular exercise--a process called atrophy wherein muscle tissue is wasted away. In laymen's terms, "use it or lose it!"
Actually, losing weight is relatively easy for most people without metabolic problems (e.g., disfunctional thyroid gland). It's keeping the weight off that's the hard part and what causes weight cycling (and hence yo-yo dieting) in many people. The diet industry will continue to stay in business because most people cannot maintain their bodyweight. The solution is simple: Combine a sensible exercise and complementary nutrition plan to encourage permanent weight loss.
Unfortunately this is not the case. If you continue to perform the same workout without progression (e.g., increased loads or sets), you will inevitably continue to get the same results--a condition known as stagnation. This is where a reputable personal trainer can provide valuable knowledge and expertise in getting you on the right path to achieving your fitness goals.
The above statement is a myth because it is too simplistic. In order to gain appreciable muscle mass, relatively heavy weights (e.g., 65 to 75% 1-RM), moderate reps (e.g., 8 to 12 reps), short rest periods (e.g., less than 1 min), and compound exercises incorporating large muscle groups (e.g, squat, deadlift) is what is needed to cause the growth hormone and testosterone release necessary to stimulate appreciable muscle mass. In order to define the body, relatively light weights (e.g., 50 to 65% 1-RM), high reps (e.g., 15 to 25 reps), and isolation exercises (e.g., leg extension, leg curl) may "tone up" your muscles but at the expense of some muscle being burned in the process. In order to maintain muscle mass, it's better to continue lifting relatively heavy weights. Heavy weight training tends to burn fat due to the retention of muscle mass. A keen nutrition program in conjunction with cardio and heavy weight training is more likely to get you ripped than light weights with high reps.
Testosterone levels largely determine one's gain in muscle mass from training. Studies have shown that women produce only about 10 percent of the testosterone that men produce, which significantly reduces their potential to gain considerable muscle size. On the other hand, women should perform strength training to at least maintain a lean physique. Strength training improves body composition by reducing fat mass while increasing lean body mass (i.e., muscle). Bottom line: women should train no differently than men when it comes to strength training. Thus, squats, bench presses, deadlifts, pull-ups, pushups, etc. are exercises all women should perform to look sexy and strong!
Feeling sore, an indication of what's known as delayed onset muscle soreness (DOMS), is not required in order to gain muscle mass, tone up, etc. What's important is that your workout is productive and intense enough to stimulate more strength in your muscle tissue, nerves and bones.
If this were true, shouldn't there be more people sporting flat stomachs in the world? If seems everywhere you look in the gym, you'll see somebody doing abdominal crunches--it's a ubiquitous exercise for sure. Unfortunately, the reality is crunches do not flatten the stomach. Instead, the exercise will help to strengthen your core muscles (e.g., rectus abdominus) under that layer of fat tissue called subcutaneous fat. In other words, crunches will get your abs stronger but will not burn your belly fat (see the spot reduction myth above). A healthy, clean nutrition plan will help to reduce the fat around your midsection and allow your hard-earned six-pack to appear.
This myth most likely got started when physique competitors began eating less food (i.e., low carbs) while doing cardio in an effort to lean out. It's not the cardio that is the culprit but rather caloric intake that's really at issue here. Of course cardio may become a factor when it is performed for over an hour every day of the week. But in most cases, the decrease in muscle mass is more likely to be attributed to not eating enough food to accommodate the hard training. Adequate protein (i.e., whey protein shakes post-workout) is especially crucial to maintain muscle mass when caloric intake decreases.
This myth got started from a study which indicated eating soy may increase estrogen within the body. But all of the hoopla needs to be taken down many notches because the amount of soy needed for this to happen was not emphasized. In other words, one would have to eat large amounts of soy protein every day for estrogen levels to increase. Most people don't eat nearly enough soy for this to occur.
This provides an easy excuse for why you're not losing bodyfat. It takes hard work, dedication, discipline, and most of all, consistency when it comes to leaning out. Your nutrition, cardio and weight training needs to be well-planned and adhered to in order for progress to be made. We all have the capacity to accomplish our fitness goals but the key is hard work and some sacrifice to get there.
This myth will not die! Weight loss should never be confused with fat loss. The weight scale only displays body weight, not fat weight. I'm always entertained by many gym goers who weigh themselves before and after weight training. They believe by what the scale shows that they're losing fat weight when in reality they're losing water weight. There's no way you can burn an appreciable amount of bodyfat from just one training session but you can become dehydrated and therefore lose water weight. I bet the same people who believe you can burn bodyfat from each training session also believe you can accelerate the fat burning process by wearing a sweatshirt while working out. Please! Again, the weight lost is water weight, not fat weight. The best way to ascertain whether or not you're burning bodyfat is to perform a skinfold assessment or simply look in the mirror. The mirror does not lie. How you look tells the story.
Ah, if only it was this easy--everyone would have ripped abs for the summer if this was true! The reality is that eating foods labeled as "low-fat" or "fat-free" may actually make you fatter. Why? Because these foods tend to have more sugar, salt, preservatives, and chemicals than regular foods in order to make them as palatable and to increase shelf life. Remember fat makes food tasty and rich. The manufacturers are compelled to add sugar and sodium to "low-fat" and "fat-free" foods to sell their products. Unfortunately, high carbs (from added sugar) and excess sodium (from added salt) wreak havoc on a lean diet. Highly processed foods may actually reduce one's metabolism when consumed regularly and make the process of leaning out even harder. Instead, eat a cheat meal at least once per week to satisfy your craving for sweet or fattening foods. This way, you'll less likely want to overindulge in decadent foods.
Absolutely! In fitness training parlance this concept is referred to as "cross training". I highly recommend you do any of the following:
-DECREASES FAT MASS
-MAY DECREASE LEAN BODY MASS (if excessive)
-MAY DECREASE FT FIBER AREA / ST FIBER AREA
-MAY INCREASE MUSCLE FIBER SIZE
-INCREASES INSULIN SENSITIVITY / GLUCOSE UPTAKE
-INCREASES PARASYMPATHETIC STIMULATION
-DECREASES EPINEPHRINE / NOREPINEPHRINE RELEASE
-DECREASES CORTISOL RELEASE
-INCREASES BONE MINERAL DENSITY (i.e., high-impact wt-bearing exercise)
-INCREASES BONE STRENGTH (i.e., high-impact wt-bearing exercise)
-INCREASED BONE MASS (i.e., high-impact wt-bearing exercise)
-IMPROVES BALANCE / AGILITY / GATE
-INCREASES STRENGTH (i.e., high-impact wt-bearing exercise)
-INCREASES FLEXIBILITY (ROM)
-INCREASES BIOMECHANICAL EFFICIENCY
-DECREASES REACTION DURATION
-DECREASES RECOVERY DURATION
-INCREASES ADAPTATIONS (e.g., specificity, overload)
-INCREASES ENERGY LEVEL
-INCREASES CAPILLARY DENSITY
-DECREASES TOTAL CHOLESTEROL
-DECREASES LDL CHOLESTEROL
-INCREASES HDL CHOLESTEROL
-INCREASES HEART CONTRACTILITY
-INCREASES MYOCARDIAL EFFICIENCY
-DECREASES SUBMAXIMAL EXERCISE HR
-DECREASES RESTING BLOOD PRESSURE
-INCREASES STROKE VOLUME
-INCREASES CARDIAC OUTPUT
-INCREASES HEART CHAMBER SIZE
-INCREASES BLOOD VOLUME
-DECREASES PERIPHERAL RESISTANCE
-INCREASES BLOOD VESSEL CROSS-SECTION AREA
-INCREASES VENTRICULAR VOLUME
-DELIVERS OXYGEN TO MUSCLES
-INCREASES TIDAL VOLUME (normal breathing capacity)
-INCREASES PULMONARY DIFFUSION CAPACITY (i.e., alveolar membrane)
-INCREASES ARTERIAL-VENOUS OXYGEN DIFFERENCE
-INCREASES MUSCULAR OXIDATIVE CAPACITY
-INCREASES MAXIMAL OXYGEN UPTAKE RATE (esp. interval training)
-INCREASES METABOLIC RATE
-INCREASES FFA MOBILIZATION
-INCREASES ENERGY STORAGE CAPACITY (e.g., glycogen, triglycerides)
-INCREASES FUEL SUBSTRATES (e.g., ATP, CP, glycogen)
-INCREASES LACTIC ACID THRESHOLD
-INCREASES MITOCHONDRIAL DENSITY (increases ATP production)
-INCREASES FUEL-BURNING EFFICIENCY (e.g., fat)
-INCREASES ANAEROBIC ENZYME ACTIVITY (e.g., phosphogen, glycolytic systems)
-INCREASES AEROBIC ENZYME ACTIVITY (e.g., oxidative system)
-INCREASES GLUCOSE TRANSPORTERS (e.g., GLUT-4)
-INCREASES MYOGLOBIN CONCENTRATION
-EXPELS WASTE PRODUCTS (e.g., lactic acid) FROM MUSCLES
-IMPROVES CONCENTRATION / FOCUS
-IMPROVES SLEEP QUALITY
-INCREASES MENTAL RELAXATION
-DECREASES MENTAL DECLINE
CHRONIC DISEASE RISK:
-DECREASES TYPE-2 DIABETES RISK
-DECREASES HEART DISEASE RISK
-DECREASES CANCER RISK (e.g., colon, breast)
-DECREASES ARTERIOSCLEROSIS RISK
-DECREASES OBESITY RISK
-DECREASES STROKE RISK
-DECREASES GALLBLADDER DISEASE RISK
-DECREASES ALZHEIMERS DISEASE RISK
QUALITY OF LIFE:
-DECREASES MORTALITY (i.e., increases life expectancy)
-DECREASES RISK OF FALLS
-DECREASES FRACTURE RISK
-DECREASES DIGESTION DURATION
Cardio per se is not the problem. In fact, cardio exercise may enhance muscle mass because it can reduce delayed onset muscle soreness (DOMS), improve sleep quality, and increase one's tolerance for intense weight training. Cardiovascular exercise promotes blood vessel dilation, ideal for increased nutrient delivery to and waste products from muscle tissue--this is what may reduce DOMS. Sleep quality can be enhanced because the body will need restful sleep in order to recover from the energy expended during cardio. Weight training intensity may be increased when performed in conjunction with cardio because one's aerobic capacity may increase, allowing for lessened rest period durations between sets.
The real issue here is over-training and/or dieting. Over-training occurs when one performs physical activity at frequencies, intensities, and/or durations that overly taxes the body's ability to recover. Dieting in this context means caloric reduction. Over-training and/or dieting are not conducive for muscle anabolism (growth). Rather, muscle breaks down (catabolism) as the body resorts to its protein stores for much-needed energy.
So the key here is to perform cardio exercise in moderation and eat plenty of carbs and protein to spare muscle tissue. Moderation means three to five days per week at 65-85% MHR from 20 to 45 minutes. Recommendations for how much in the way of carbs and protein one should eat to preserve muscle mass can be found in the nutrition section of this blog.
A small study published in Medicine & Science in Sports & Exercise had found that it does NOT matter what order you perform cardio and weight training in the long-term. Muscle gains may be less if you perform cardio first (most likely due to pre-fatigued muscles) although in the long run, this effect is insignificant. Nevertheless, as a personal trainer, I prescribe the order of exercise (cardio or weight training) relative to a client's fitness goals. Thus, if your objective is to lose bodyweight or bodyfat, you should prioritize cardio and do it first. On the other hand, if your goal is to increase strength, you should perform resistance training first while you have the most energy. If you have limited time to workout, bike to the gym and count this as your cardio workout. Plus, it's a great warmup exercise prior to hitting the weights.