Monday, June 11, 2018

Pro Tips for Getting the Most Out of Your Next Fitness Conference

Going to a fitness conference not only elevates your education and keeps you up to date on exciting trends, it’s a lot of fun! And being able to collect multiple CEUs all in one place is convenient, cost-effective and time-efficient. However, attending a major fitness conference can quickly become overwhelming if you’re not prepared. Whether you’re taking part in a big conference for the first time or looking for new hacks to keep you at the top of your game, here’s what you need to know for getting the most out of your next education event.

Session Selection

Before you even get to the conference, you’ll have to select online which sessions you want to attend. Register early to ensure session availability. In theory, you might think it’s best to attend as many movement workshops as possible. In practice, this approach can be exhausting. When you’re physically fatigued from working out all day, you’re more likely to forget all that you saw and learned. On the flip side, sitting in too many back-to-back lectures could make you feel restless or drowsy.

With that in mind, consider how you can balance exercise and downtime during the conference. To ensure your schedule has enough variety to keep you energized, opt for some workouts and some lectures each day, or a mix of light and intense movement sessions. Conferences are the perfect time to experience new formats and education, so avoid signing up for just the most obvious choices. Branch out!

Packing

Whether you’re travelling to an event or attending one close to home, be sure to pack your day bag with a few essentials. You’ll want a reusable water bottle and plenty of healthy snacks. Lineups to buy food at conference sites can be long, and the options are sometimes unappealing, so it’s good to have healthy foods on hand to tide you over until lunch/dinner or as fuel when hurrying from one session room to another. If you’re traveling from out of town, hit a grocery store the day you arrive to stock up on food you can store in your hotel room.

Other must-pack items include a phone charger, a change of clothes if you’ll be doing multiple workouts in one day and anything you’d need to keep warm in an air-conditioned convention hall and lecture rooms: jacket, sweatshirt, warm-up pants, etc. Some conferences take place primarily or partially outdoors or even on a ship, such as the annual Zumba Cruise. In that case, pack sunscreen and a sunhat and keep your water bottle close by to stay hydrated. For back in your hotel or cruise-ship room, you might also appreciate having exercise recovery tools on hand, such as a foam roller.

Attending Sessions

One of the best ways to retain information is to take notes, so come prepared with a pen/paper, laptop or iPad. Many conferences provide session handouts that you can either print up on your own or save as digital files.

Performing the exercises in movement sessions is a great way to test-drive what’ll work in your classes or with clients. Since it’s easy to forget exercises and sequences once you leave the session, plan to either take intermittent notes throughout a workshop or jot down ideas immediately afterward when they’re still fresh in your mind.

Although most conferences don’t allow you to take video during sessions, you could ask a friend or fellow attendee after the session to film you doing a few exercises or routines you just learned. Having these videos stored on your phone will remind you of exercises to try in your classes and with clients back at home.

Expo Hall / Tradeshow

Depending on the size of the conference, you might find that cruising the Expo Hall takes considerable time and energy. It’s helpful to do a preliminary lap of the tradeshow just to see what’s there. Then take a second and third tour of the space, stopping at the booths that interest you. Schedule time to visit the Expo Hall multiple times during the conference to ensure you didn’t miss anything interesting during previous rounds.

The more prepared you are for all there is to see and do at a fitness conference, the more you can soak in the experience and leave with a slew of ideas—and enjoyable memories!—to advance your fitness career.

 

Don’t miss out on this year’s NASM Optima Conference! Register now at www.nasmoptima.com

 


Pro Tips for Getting the Most Out of Your Next Fitness Conference posted first on http://blog.nasm.org

How to Prevent Diastasis Recti (with Crunches)

Diastasis recti abdominis (DRA), commonly shortened to diastasis recti or diastasis, is the separation of the rectus abdominis down the linea alba. While it is a terrifying thought for most, DRA is a reality for up to 70% of pregnant and postpartum women (Hakan, 2018). Though it can also occur in men who carry excess abdominal fat, the condition is most commonly associated with women during and after pregnancy as a result of hormonal shifts and the continual stress placed on the core from carrying a baby to term. DRA has become a hot topic as more and more fitness professionals advertise programs that promise to prevent or fix the condition. These programs have introduced several strong opinions into the discussion including avoiding crunches and the prone position or abstaining from core exercises during pregnancy and postpartum. These ideas are widely circulated which has influenced the perception of exercise during the pre- and postnatal period. Unfortunately, many of the common recommendations for addressing DRA are based on grains of truth or best guesses and do not take into consideration much of the recent research. This article provides a brief overview of the common misconceptions, a synthesis of the latest studies, and recommendations for helping clients beat the statistics and avoid diastasis.

The typical assessment for diastasis is performing a slight abdominal crunch while palpating with two fingers above and below the belly button to feel for a separation of the abdominal wall. A one finger width or smaller is normal, but anything larger than two fingertips is considered DRA. In recent years, crunches have been considered off limits for pregnant and postpartum women. They have been criticized by many bloggers and fitness professionals citing possible strain on the spine as well as increased abdominal pressure. Instead of the crunch, clients have been encouraged to “draw in” their navel to their lower back or “suck in” their belly during exercise. As with many recommendations, there is a bit of truth to these ideas. It is true that pulling on the neck can strain the spine (flexion itself does not), excessive intra-abdominal pressure should also be avoided, and it is best for the core muscles to stay engaged during physical activity. However, recent studies have shown that the generalized advice that women frequently receive, without detailed guidance, can often do more harm than good — especially for those with DRA. Crunches, or curl-ups as they are called in the scientific literature, are safe and effective for strengthening the core when performed correctly (Schoenfeld & Kolber, 2016). They also typically do not need to be avoided during pregnancy or postpartum as commonly suggested. Whereas simply drawing in the belly toward the spine can increase pressure down the midline of the abdominals widening the inter-recti distance (IRD), also called “the gap.” (Mota, Pascoal, Carita, & Bo, 2015). In fact, many studies published in the past few years have reached the same conclusion, the drawing in maneuver adds to the strain on the linea alba, resulting in increased IRD, while the curl-up closes the gap. Science has proven that crunches and other common core exercises can be used to both prevent and treat DRA.

While it would be nice to end there, the human body is incredibly complex which means that issues like diastasis recti are rarely black and white. Even though crunches have been proven to be effective to strengthen the core and close the gap, a study using ultrasound technology showed that they may also distort the linea alba in people with DRA. However, when performed after engaging the transversus abdominis (TrA), the distortion was reduced or eliminated (Lee & Hodges, 2016). This finding reinforces the idea that crunches are not inherently good or bad, but like most exercises, they must be taught and performed correctly to reap the benefits. While making subtle adjustments is necessary, many expectant and new mothers unnecessarily cease all core exercises in an effort to prevent DRA because of the confusion and controversy surrounding the topic. Preventing diastasis is far easier than attempting to fix the problem after it has occurred. Allowing core muscles to atrophy for nine months (and then followed by several months postpartum) increases the chances of muscles separating under the strain of pregnancy and delivery. The conflicting advice does women a disservice because maintaining a strong core and healthy weight with exercise before, during, and after pregnancy is undoubtedly the best method to avoid DRA.

There are a few additional points to consider when helping women prevent or heal diastasis. Since it is not typically advised for women to exercise flat on a hard surface after the first trimester, gentle crunches on a stability ball or a slightly inclined bench are convenient alternatives to the mat. Core strength can also be accomplished by performing deep breathing exercises, pelvic tilts, planks, modified pushups and other bodyweight exercises that engage the abdominals. It is important to avoid deep twisting through the midsection and quick twisting movements like bicycle crunches that add additional stress to the already stretched abdominal wall during and soon after pregnancy. Proper breathing is a critical component for keeping the core strong and avoiding excess strain. The Valsalva maneuver, holding the breath and bearing down commonly associated with crunches, heavy lifting, and other strenuous exercise, creates excess intra-abdominal pressure which can cause serious problems with the core and pelvic floor. Exhaling on the exertion of any movement can alleviate pressure on the abdominals as well as the pelvic floor. Lastly, each exercise should begin with proper alignment to consistently reinforce good posture, promote hip stability, and correct muscle imbalances. Avoiding excessive anterior pelvic tilt or “sway back” will lessen the strain on the abdominal wall and lower back. Mothers returning to exercise after giving birth should ease back into training with a focus on restoring neutral alignment as well as rehabilitating the core and pelvic floor rather than weight loss or intensity. Recent studies have shown that exercise, including curl-ups with an activated TrA, can help close the gap and increase core strength. The research is now shifting more toward optimizing core function, alleviating pain, and improving quality of life. Successfully healing severe cases of diastasis continues to be a challenge which is why encouraging pregnant women and new moms to prevent DRA by maintaining a strong core and dispelling myths about pre- and postnatal exercise is essential.

 

Top 8 Exercises to Prevent Diastasis Recti:

Modified Crunch: Manually pulling rectus abdominis muscles together

Lie on back with bent knees and feet flat on the floor. Use hands or wrap a towel or belly band around the waist to pull the abdominal muscles together. Inhale deeply to expand the belly. Slowly exhale while contracting the abdominals, pulling them inward, and raise head off the floor. Return to the starting position and repeat.

Pelvic Tilt with Crunch on Ball

Start by sitting on a well-inflated stability ball, then slowly roll down until it fits comfortably on the lower back. Be sure the body feels balanced, placing the feet directly under the knees. Stabilize the neck by gently supporting the head. Exhale and roll shoulders slightly up off of the ball in a crunch. During the crunch, the hips press up and away from the ball while squeezing lower abdominals, glutes, and pelvic floor. Inhale and slowly return shoulders and hips to the start position. Be careful the ball does not slip out! This is a very short range of motion. Do not relax abdominals or stretch over the ball; the core should remain engaged throughout the exercise. If this is too complicated to start, just focus on the crunch without a pelvic tilt.

Modified Pushups

Start in a kneeling pushup position with the back/neck straight and core tight. Place hands in line with the chest, and wider than the shoulders. Slowly bend the elbows and lower toward the floor. Be sure not to sag the lower back down or raise hips too high. Press back up to starting position and exhale. If pushups hurt the wrists, they can be done on the fists/knuckles, using pushup handles, or grip dumbbells to keep wrists straight.

Plank

Lie in a prone position on forearms with elbows positioned under shoulders, on toes or kneeling. Draw abdominals in tight — bracing the belly. While maintaining the abdominal contraction, tighten glutes, pelvic floor, and inner thighs, and hold body straight. Never sag the hips. Raise hips or take a break if needed. Form is more important than how long it is held. The core remains tight the whole time, and breathe steadily.

Hip Circles on Ball

Sit on the ball with good posture. Move hips in small circles to the right. Try to use the core and not the legs. Then slowly move hips to the left. Then forward and back. Keep core tight and breathe normally.

Cat Pose

Start on all fours with hands aligned directly beneath shoulders, and knees directly beneath hips. Begin by drawing in the abs, slowly exhaling, and rounding spine toward the ceiling. Release the rounded spine and drop the belly toward the floor while relaxing the abdominal muscles. Repeat with each breath.

 

Opposite Arm and Leg Extension

Begin on all fours with back straight, hips level, and core tight. Lift one leg straight behind, and the opposite arm directly in front. Reach and inhale. Bring knee in toward the elbow while squeezing the abs, round the back, and exhale. Complete repetitions on one side before switching.

 

Bridge on Stability Ball

The head should rest comfortably on the ball with the neck in a supported, neutral position. Hips, knees, and ankles should be aligned at a 90-degree angle. Lower the hips toward the floor, and then lift the hips slowly. If moving the hips is not comfortable on the lower back, simply hold the top position or try tucking the pelvis to lengthen lower back muscles. Keep the knees over the ankles, not in front of toes. The ball should not move during the exercise.

The science is conclusive that the safest and most effective strategy for preventing diastasis is with consistent physical activity, weight management, and core strengthening exercises (including crunches) throughout a healthy pregnancy and postpartum. Please leave your thoughts in the comments. Do you have a question about diastasis? Have you experienced DRA yourself or with a client?

Want to learn more on exercise and pregnancy? Visit these links for blogs, CEUs and articles from NASM and AFAA:

Exercise and Pregnancy: Physiological Changes and Exercise Programming

Exercise and Pregnancy: Women Taking the Lead in Their Workouts

Helping Moms (and Moms-To-Be) Keep it Strong: The Pelvic Floor

NASM Women’s Fintess Specialization

American Fitness Magazine: Fitness for Two CEU Corner

AFAA’s Perinatal  Fitness Course

 

References:

Hakan, K. (2018). Umbilical Hernia Repair and Pregnancy: Before, during, after…. Frontiers in Surgery, 5(1).

Lee, D. & Hodges P. (2016). Behavior of the linea alba during a curl-up task in diastasis rectus abdominis: An observational study. Journal of Orthopaedic & Sports Physical Therapy, 46(7), 580-589.

Mota, P., Pascoal, A., Carita, A. & Bø, K. (2015). Inter-recti distance at rest, during abdominal crunch and drawing in exercises during pregnancy and postpartum. Physiotherapy, 101.

Schoenfeld, B. & Kolber, M. (2016). Abdominal Crunches Are/Are Not a Safe and Effective Exercise. Strength and Conditioning Journal, 38(1), 61-62.


How to Prevent Diastasis Recti (with Crunches) posted first on http://blog.nasm.org

Thursday, June 7, 2018

HIIT, HVIT, or VIIT: Which IT are you doing and do you know the differences?

pes-2

High-intensity interval training (HIIT) is all the rage in the fitness world. No doubt you’ve seen various benefits touted just about everywhere, but what is the actual science behind this training design?  Would a high-volume interval training (HVIT) approach better meet training goals, or perhaps a combination approach of variable-intensity interval training (VIIT)?  Discover the differences and how to apply the variables of quality and quantity of movement for better results.

Look just about anywhere in fitness these days and you’d be hard-pressed to miss some program, product or menu advertising high-intensity interval training (HIIT). So why are these programs trending and so popular? One undeniable fact is the time-efficiency in which an individual can achieve comparable results to those attained through higher-volume, lower-intensity workouts (4). Research demonstrates similar results with up to 90% less training volume and up to 67% less time commitment (5), and in an era where time has become such a precious and valued commodity, the popularity of HIIT comes as no surprise.

Studies also demonstrate how this training modality is not solely limited to improving fitness markers (e.g., aerobic and anaerobic performance), but delivers positive health improvements like blood pressure and glucose sensitivity (6). Regardless of this research, perhaps the most influential driver of this trend still lies with the perception that HIIT training increases overall caloric burn between the combined effects of the session and the excess post-exercise oxygen consumption (EPOC or afterburn).

Unfortunately, perception and reality are not always the same, and as fitness professionals, we hold the responsibility of educating clients and club members to the truth. Nonetheless, individuals continue to flock in droves to HIIT workouts and programs that they (a) don’t thoroughly enjoy, but perhaps tolerate in the hopes of achieving some desired transformation, or (b) shouldn’t undertake given their lack of adequate preparation (levels of stability and mobility) or conditioning levels. Considering the latter point, it should be concerning that chronic or overuse-type exercise-related injuries in recreational and sports facilities have increased by an average of 4% over the past 10 years (7).

There is also a general lack of understanding within the fitness industry of what truly constitutes HIIT training and what it is intended to accomplish. What many describe as HIIT is more likely high-volume interval training (HVIT) or, in a best-case scenario, variable-intensity interval training (VIIT). Each can be effective as long as the practitioner understands their unique purpose and programs accordingly. As professionals, it is imperative to understand that extreme conditioning programs (i.e., training hard rather than smart) are more often than not, an unwise approach to programming for most individuals. Bergeron and colleagues (8) state that many characteristics of these conditioning workouts disregard current standards for developing muscular fitness which is concerning. For example, repetitive, timed, maximal or near-maximal efforts incorporating short or insufficient recoveries, a characteristic of many popular HIIT programs, may predispose individuals to overreaching or overtraining that can elevate oxidative stress and cellular damage beyond autophagy (i.e., above exercise’s natural ability to remove biological waste products or cellular debris); suppress immune responses, and impair exercise technique; consequently increasing the risk of musculoskeletal strain and injury. The focus of this article is to help differentiate between these three training modalities by reviewing key bioenergetic and programming principles, and to create a sense of purpose and appropriateness behind whichever modality is aligned with the client’s or group’s unique needs and desires.

The Energy Pathways

One common misconception about energy pathways is the belief that the anaerobic systems only contribute during high-intensity exercise when our ATP demand exceeds the maximal capacity of our aerobic pathway. In reality however, they are always contributing to the energy we need by providing immediate energy at any point of time during any change in activity or exercise intensity (e.g., interval training, sitting to standing, walking to initiating a light jog). Now consider the following points:

  • The origins of true HIIT lie within sports conditioning and hold an explicit purpose – making athletes bigger, stronger, faster and more explosive by implementing overload and specificity to training, For example, a power athlete performing a 225 lb.1RM power clean would train at near maximal loads and rates to improve his maximal performance and not train with 125 lbs. for higher repetitions or longer durations. Near-maximal loading and rate training constitutes HIIT, whereas 125 lb. set stimulates power endurance or submaximal performance, which is not HIIT, but HVIT. Likewise, a wide receiver running a 4.5-second, 40-yard dash would train at near maximal speed with a goal to improve upon his 40-yard time and not perform a high-volume of continuous bouts at 6-seconds because that is the pace he can sustain.
  • In essence, never confuse maximal performance with maximal effort as they are very different. The above-mentioned examples of improving performance (1RM, fast 40-yard dash) represents performance – intensity, whereas the sub-maximal, sustained work (e.g., anaerobic capacity, power endurance) represent something else – volume.
  • Human capacity to sustain intense bouts of work that rely significantly upon the two anaerobic pathways (i.e., capacity of fast glycolytic – primarily, and the phosphagen system) is generally between two to three minutes for most individuals (Table 1-1). Work intervals exceeding these durations regardless of whether it is performed as one continuous exercise or as a circuit will progressively rely more upon the aerobic pathway and mandate lower-exercise intensities. For example, leg ergometry studies demonstrate 96% contribution of energy from the anaerobic pathways with 10-seconds of work (sustaining almost 100% of maximal power output); 75% contribution at 30-seconds (sustaining 75% of maximal power output); 50% contribution at 60-seconds (sustaining 35% of maximal power output) and only 35% contribution at 90-seconds (sustaining 31% of maximal power output) (9, 10).

table 1

  • Although the anaerobic pathways provide an immediate, but limited supply of energy, they recover very slowly once exhausted.
  • The time-delay to achieve steady-state (aerobic dominance) generally takes between 90-seconds and 4-minutes, depending upon the modality and intensity of the activity, and the exerciser’s conditioning level – explaining in part why the use of heart rate during non-steady-state or interval training to measure intensity is generally invalid.

Considering the general nature of most interval-type workouts, this article will briefly review key bioenergetic concepts of the fast glycolytic pathway (glycolysis) or lactate system, and not the phosphagen system. By definition, glycolysis represents the metabolic pathway that breaks down glucose (from muscle glycogen) into two pyruvate molecules (12). While pyruvate is technically the end product of glycolysis, it experiences two fates; either being shuttled into the mitochondria for aerobic respiration or being converted to lactate in the absence of adequate oxygen. What is important to remember is that the fate of pyruvate does not follow an all-or-nothing principle (i.e., it can progress to both simultaneously, depending on the availability of oxygen). The quantity of pyruvate that enters the mitochondria is contingent on the capacity of the aerobic pathway (e.g., availability of oxygen, size and number of mitochondria). Any excess pyruvate that cannot pass to the mitochondria are converted to lactic acid that quickly dissociates into lactate and a hydrogen ion because lactic acid is not stable in an aqueous environment (and many body tissues are composed of water).

The small amounts of ATP manufactured during glycolysis are utilized by the muscle cells which simultaneously also produce hydrogen ions as ATP molecules split. Normally, these hydrogen ions are passed to the mitochondria during aerobic respiration, but under non-steady-state (anaerobic) exercise, these ions are produced very rapidly and may not all be capable of passing to the mitochondria. Unfortunately, any accumulation of hydrogen ions results in metabolic acidosis within the muscle tissue (lowering tissue pH levels). This acidosis produces an inhibitory effect on of many glycolytic enzymes (making less energy available) as well as impeding calcium’s ability to enable muscle contraction within the cell. Consequently, these hydrogen ions must be removed from the cell to allow it to continue working. The combination of pyruvate with two hydrogen ions to form lactate (plus hydrogen) can be cleared from the muscle cell into the blood. The accumulation of hydrogen ions within the cells is also believed to increase pain receptor sensitivity within muscles, offering an explanation why individuals experience a muscle ‘burn’ during high-intensity exercise.

The human body is constantly producing lactate given how certain cells (e.g., red blood cells) lack mitochondria. At rest and under steady-state exercise conditions, the body maintains a balance between lactate production and its removal as lactate can be converted back to pyruvate and then converted back to glucose or used as a fuel (13). The hydrogen ions spilling into the blood are buffered to prevent blood pH changes which could potentially damage various circulating proteins (e.g., red blood cell, white blood cells, hormones, enzymes) (Figure 1-1). A unique function of sodium bicarbonate (NaHCO3) is that it acts as our principal hydrogen buffer. As illustrated in Figure 1-2, sodium or potassium in the blood binds with lactate to form a compound that can enter the cell for use as a fuel. The remaining bicarbonate binds with hydrogen to form carbonic acid (H2CO3), a weak acid that then dissociates into water and carbon dioxide. Although we have no real need to remove this metabolic water from the body, the carbon dioxide can be expelled via the lungs.

Figure 1-1: Lactate and hydrogen clearance into blood

Fig 1.1

While cells spill lactate and hydrogen into the blood that is subsequently buffered, it is simultaneously regenerating this buffer using sodium, water and carbon dioxide. The moment at which the rate of lactate buffer regeneration fails to maintain pace with its rate of depletion is termed Onset of Blood Lactate Accumulation (OBLA), a term sometimes referred to as lactate threshold by practitioners although they are not technically the same. At this point, the blood can no longer accept hydrogen ions as it needs more time to regenerate its buffer. Consequently, hydrogen ions now accumulate within the muscle cell, impairing its ability to perform biological work. The key takeaway for practitioners to understand is that this energy system is not limited by what the muscle can or cannot do, but by the capacity of the blood to buffer and regenerate its buffer. Therefore, a circuit targeting different muscles where one believes may enable greater work-rates over the duration of the session may still prove to be problematic given how each muscle is clearing lactate into the same bloodstream. The limiting factor when training this energy system has more to do with the time needed to regenerate the lactate buffer within the blood and less to do with the muscles themselves.

Figure 1-2: Buffering protons with sodium bicarbonatefig 1.2

Note: It is important to note that the major function of this process is to buffer hydrogen ions with sodium bicarbonate that can then be released as CO2 and H2O.

Training the Fast Glycolytic System

Few studies have provided results that can be used to generate definitive guidelines for choosing specific work-to-rest ratios where the lactate buffer can regenerate itself sufficiently to tolerate another high-intensity work interval. As mentioned previously, the principles of specificity and overload must be applied appropriately by manipulating key programming variables (FITR – frequency, intensity, training interval, recovery interval). As this system generally begins to contribute significantly after 10 – 15 seconds and lasts approximately 2 – 3 minutes in most individuals, the guidelines provided in Tables 1-2(a) and 1-2(b) can serve as a programming template to start (11).

Table 1-2(a): Training Variables for the Fast Glycolytic System

Typical Bout Duration % Maximal Performance ** Work-to-Recovery Interval ** Type of Recovery
Start with 30 sec * 75 – 90% 1:2 – 1:3 Active (light loads)
* Should ultimately match needs of the individual, sport or goals of the program.** This should not be confused with % of maximal effort as one experiences fatigue.

 

Table 1-2(b): Recovery Variables for the Fast Glycolytic System

Recovery between Workouts Training Sessions per Week Complete Energy System Recovery
48 hours 2 – 3 x Blood lactate return to baseline within 30 – 60 minutes following intense exercise.

If the recovery interval is inadequate, this system gradually depletes itself over successive repetitions to the point where desired intensities can no longer be sustained. As mentioned previously, continuing to train under compromised conditions must then be questioned given the diminished training efficacy and increased potential for injury. Many popular workouts today incorporate intervals that target this energy pathway, but fail to accommodate appropriate recoveries. For example, a coach may implement 60-second work bouts with only 30-second recovery intervals and wonder why the work rate is diminishing by the 4th or 5th minute (not differentiating performance from effort). However, if the coach realized that the fast glycolytic system can only sustain 2 – 3 minutes of work at 75 – 90% of maximal performance, he or she may implement 60-second intervals with perhaps a 30-second recovery for 3 intervals, then take a 2½ to 3-minute light-active recovery, before repeating this format. Each aggregated set would equal 180-seconds of work (3 x 60-seconds) at which point work rate is most likely no longer sustainable, thereby justifying a longer recovery to regenerate the blood’s buffer in order to maintain higher-intensity (performance, not effort) work rates. Recoveries should always be active (light movement) and involve the exercising muscles as this helps expedite hydrogen and lactate out of the cells and into circulation.

Gender Differences

Over recent years, researchers have begun examining bioenergetic differences between men and women (14, 15). Given how women generally have lower concentrations of type II fibers than men (fibers more responsible for anaerobic respiration), it is believed that they have a lower capacity for anaerobic exercise in comparison to men. This assumption is further supported by smaller blood volumes, thus holding smaller quantities of lactate buffer, in females. There has also been new research into the role of estrogen and the anaerobic pathways. Estrogen is believed to reduce the efficiency of enzymes involved within these pathways, reduce the rate of energy production and reduce the rate of conversion of pyruvate to lactate which slows lactate clearance from the muscle. Collectively, these factors diminish the overall efficacy and efficiency of the anaerobic pathways in women, which merits consideration for programming. Although no clear guidelines exist, the overall takeaway is that intervals for women should most likely not be as challenging as they are for men (as measured by absolute power production – watts, or load); the work intervals probably need to be shorter in duration given their reduced ability to produce and clear lactate as quickly, but the recovery intervals can be shorter in duration (e.g., 1-to-2 work-to-recovery ratio or less) as the amount of lactate buffer to be regenerated is smaller.

EPOC or Afterburn

The additional calories expended through EPOC is another myth often marketed with these programs. The unfortunate reality is that the role of EPOC in weight loss is largely unsubstantiated (16). It has been concluded that exercise intensity (HIIT) has a greater role in EPOC variability compared to exercise duration or volume (HVIT) (17). Knab and colleagues (18) studied ten male participants who completed two separate 24-hr visits to a metabolic chamber (one exercise and one rest day). The exercise day consisted of 45-minutes of cycling at an intensity of 73% of VO2max (generally regarded as higher-intensity with heart rates over 85% of maximal performance). The exercise bouts expended 519 kcal and EPOC remained elevated above resting levels for 14 hours post-exercise, resulting in an impressive total of 190 kcal (13.5 kcal per hour average or a little over half a Starburst™ candy). Accumulated three times a week over 52 weeks amounts to 8½ lbs. in one year, but it is important to note that the intensity of exercise performed by these participants was vigorous and unlikely to be continuously sustained by most individuals for 45 minutes. Studies involving more moderate volumes and moderate intensities only produced the equivalent to ½ – 3 pounds of additional energy over the period of one year. The general conclusion on EPOC is that is only generates approximately 7% of the total energy expenditure of exercise. For example, a workout burning 300 kcal may only yield 21 EPOC calories. While EPOC may be limited in its contribution to weight loss, it has been suggested that the cumulative effect of the EPOC over a 1-year period may be the energy expenditure equivalent of up to 3 pounds of adipose tissue (17). Consequently, while the true HIIT workout in Figure 1-3 expended fewer calories in the workout than the HVIT illustrated in Figure 1-4, it may produce a higher EPOC in recovery which may negate any calorie difference between the two workouts, although the injury potential differential still exists (i.e., higher with HVIT).

Programs

Figure 1-3 illustrates an example of a true HIIT workout, characterized by work intervals performed at the same intensity throughout the entire training session. For example, if each workload consumed 20 kcal over the 60-second interval, and followed a 1-to-3 work-to-recovery ratio where each minute of active recovery expended 5 kcal, then one entire interval would expend 35 kcal over 4-minutes (20 kcal for work + 3 x 5 kcal for recovery). Over the period of a 20-minute workout, this individual would complete 5 intervals (and 5-total minutes of work) and expend a total of a 175 kcal.

Figure 1-3: A true HIIT workout

HIIT 1.3

Appropriate recoveries = consistent work performance and consistent calorie burn over successive intervals. 4-min x 5 sets equals 20-minute workout, and breaks out as follows:

  • 60-sec HIIT = 20 kcal/min.
  • 180 second recovery = 5 kcal/min x 3 = 15 kcal.
  • One interval = 35 kcal x 5 intervals.
  • Total workout = 175 kcal.

On the other hand, a HVIT workout (Figure 1-4) that many perceive as HIIT training that includes 60-second work and recovery intervals will incur a greater volume of work (100% more work), but a smaller relative differential in expended calories. For example, while the first few intervals of this workout may expend 20 kcal over the 60-second work interval and just 5 kcal during the 60-second active recovery, this caloric expenditure rate cannot be maintained over the ensuing repetitions. Consequently, while 10 intervals may have been completed the caloric differential between this HVIT and the true HIIT workout may only be marginal, but the risk of injury in the latter intervals may certainly increase.

Figure 1-4: A HVIT workout

HVIT 1.4

Inappropriate recoveries = reductions in performance and decreased caloric burn.

  • 60-second HVIT intervals #1 – 2 = 20 kcal/min.
  • 60-second recovery between each work intervals = 5 kcal/min.
  • 60-second HVIT intervals #3 – 6 = 17 kcal/min.
  • 60-second HVIT intervals #7 – 8 = 12 kcal/min.
  • 60-second HVIT interval #9 – 10 = 9 kcal/min.
  • Total workout = 200 kcal.

Solutions

In light of the information presented and summarized below in Table 1-3, is there an ideal solution to this growing trend that considers the overall concerns? Herein lies the third type of training – variable-intensity interval training (VIIT), a hybrid form of programming that incorporates the best of HIIT, while simultaneously minimizing some of the concerns associated with HVIT.

Table 1-3: HIIT v. HVIT Summary

Tab 1.3

 

As illustrated in Figure 1-5, VIIT includes pre-scripted variations in the intensity of the work intervals performed in order to attain (a) more true HIIT intervals within the overall session that follow appropriate recovery periods – improves performance and may possibly increase EPOC, yet (b) increases the training volume (increasing session caloric burn rate) and perception of work rate, while reducing the potential for injury. The program may include a few successive intervals of high-intensity work coupled with shorter recoveries representative of HVIT (e.g., 2 – 3 x 60-second work intervals using 30-60 second recovery intervals), then introduces a sequence of intentional lower-intensity work intervals that do not overwhelm the body’s lactate buffer (i.e., enable regeneration). This might involve 1 – 3 sets performed at a sub-maximal performance (below 75% of maximal performance) where the aerobic pathway contributes more significantly. The workout then returns to another series of high-intensity interval bouts before re-introducing the lower-intensity bouts. The outcome is the best of both HIIT and HVIT, without many of the concerns. Furthermore, this format may also enhance the psycho-emotional impression or experience of the training program.

Figure 1-4: A VIIT program

HVIT 1.4

However, one question remains unresolved and it pertains to maximizing work in the minimal amount of time – more specifically to the recovery intervals. Although the recovery needs to remain active to help expedite metabolites (e.g., hydrogen, lactate) out from the muscle cells, they should de-emphasize biological work of the more anaerobic type II fibers within the body in order to facilitate recovery – expediting metabolite clearance, and regenerating the blood lactate buffer. Subsequently, this offers an ideal opportunity to target the type I fibers with stabilization exercises for balance and postural control, similar to the methodology of Phase 2 training within NASM’s OPT model (Strength-endurance). As strength and conditioning coaches often do with athletes, this recovery interval provides a great challenge to athletes to demonstrate good postural control through low-active stabilization exercises to ensure good form and technique, while concurrently allowing the lactate buffer and muscles the needed time to recover. For example, a set of barbell clean and presses (performed for 45-seconds) performed as a superset with barbell side lunges (performed for 30-seconds in each direction) – total of approximately 105 seconds of work may include 210 seconds of recovery (1-to-2 work-to-recovery ratio). An active recovery preceding the next superset of barbell deadlifts and standing kettlebell rear rotational presses could be designed as follows:

  • Light movement – walking (10-seconds)
  • Plank walk-ups (20-seconds)
  • Rotational planks (20-seconds per direction)
  • Transition (5-seconds)
  • Single-leg swings with hip drivers in all three planes (30-seconds per leg)
  • Transition (5-seconds).
  • Light Turkish get-ups (20-seconds per side)
  • Transition (5-seconds)
  • Light movement – walking (15-seconds)

To summarize, true HIIT training holds a purpose of improved performance and is orientated around movement quality. What we perceive to be HIIT, but is actually more aligned with HVIT, is focused upon volume or movement quantity, and perhaps at pursuing a higher caloric expenditure. One must question the efficacy and the cost of this approach. Remember, workouts where the total work interval performed before taking a recovery interval that exceeds 3 to 4 minutes, or one that is performed at intensities below 75% of maximal performance (e.g., 75% of 1RM) or one that usually involves bodyweight resistance training is most likely HVIT (and not HIIT), and should be defined as such. However, to truly capitalize on the benefits that each can or may provide, VIIT appears to offer the ‘sweet spot’ where we can attain both needs and desires.

References:

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HIIT, HVIT, or VIIT: Which IT are you doing and do you know the differences? posted first on http://blog.nasm.org

Wednesday, May 16, 2018

Tuesday, May 8, 2018

AMTA Visits NIH to Move Massage Therapy Research Forward

Left- right: Niki Munk, Ann Blair Kennedy, and James Specker.

By Niki Munk, PhD, LMT
Massage Therapy Foundation Trustee

American Massage Therapy Association [...]

The post AMTA Visits NIH to Move Massage Therapy Research Forward appeared first on Massage Therapy Foundation.


AMTA Visits NIH to Move Massage Therapy Research Forward posted first on http://massagetherapyfoundation.org