Normal-Weight Women Lose >6kg Fat Mass in 6 Weeks With Three 15x60s HIIT Workouts/Week - Without Dieting

Normal-Weight Women Lose >6kg Fat Mass in 6 Weeks With Three 15x60s HIIT Workouts/Week - Without Dieting

high intensity HIIT interval training LISS lose fat low intensity steady state

I am still waiting for a study using only body weight exercises like squats, push ups, burpees and co as a HIIT regimen for weight or rather fat loss.

While HIIT is gaining ground especially in male muscle heads, women like the twenty-three previously untrained women (28.43 ± 12.53 years), who participated in a recent study from the Department of Sport at the School of Physical Education and Sport of the University of Sao Paulo in Brazil (Panissa. 2016), are gravitating rather towards training in the alleged (but non-existing) "fat burning" zone at an intensity of 70% of their individual HRmax.

I guess, Panissa et al. knew that, because in their latest study they compared the effects of 6 weeks of high-intensity intermittent training (HIIT) to those of moderate intensity continuous exercise (MICT-control group) on body composition (skinfold measures), hunger and food intake.

Read more about exercise-related studies at the SuppVersity

Tri- or Multi-Set Training for Body Recomp.?

Aug '15 Ex.Res. Upd.: Nitrate, Glycogen, and ...

Pre-Exhaustion Exhausts Your Growth Potential

Full ROM ➯ Full Gains - Form Counts!

BFR-Preconditio- ning Useless for Weights?

Study Indicates Cut the Volume Make the Gains!

As previously highlighted, the subjects were twenty-three previously untrained women (28.43 ± 12.53 years) who were randomly assigned to a HIIT (n = 11) or MICT group (n = 12).

• The HIIT group performed 15 1-min bouts at 90 % of maximum heart rate (HRmax) interspersed by 30-s active recovery (60 % HRmax). 
• The MICT group performed a continuous exercise at 70 % HRmax equalizing the training load method proposed by Edwards (1993) to a similar value achieved by the HIIT group. 

Training for both groups was performed on regular cycling ergometers three times per week for 6 weeks. More specifically, both groups performed the same warm up and cool down, composed by 3 min at 60 % of maximum heart rate, MICT sessions consisted of moderate intensity aerobic exercise, i.e., after warm up the subjects performed 29 min at 70 % of maximum heart rate. HIIT group performed 22 min of HIIE using a 2:1 effort–pause ratio, where the effort was 1 min at 90 % of maximum heart rate and recovery was a 30s exercise at the same load as warm up (60 % HRmax).Each training session was closely supervised, and load was adjusted according to individual HR prescription. During this period subjects were asked to avoid any supervised exercise and strenuous efforts during their daily routine.

Was the training load standardized? To equalize training load between groups, the scientists used a method proposed by Edwards (1993). He proposed a zone based method for the calculation of training load. According to Edwards model, the time spent in five pre-defined arbitrary zones is multiplied by arbitrary coefficients to quantify training load. You can read up on the method here.

The performance effects were assessed by the means of Astrand cycloergometer that were used to estimate maximal oxygen consumption (VO2max) 1 week before and after the training period.

"Feeding behavior was assessed by two methods: (1) a 3 days daily food recordatory, including 1 weekend day before the protocols at baseline and after the last session. A detailed explanation for filling the food diary was held at the end of the evaluation, to be returned completed during the first week of training. The analysis of food diaries was made from the application to FatSecret [Subar. 2010]; (2) Immediately after each training session, participants answered a Visual Analog Scale (VAS) of Hunger ranging from 1 to 10, where 1 corresponded to no sensation of hunger and the 10 maximum feeling of hunger" (Panissa. 2016).

The subjects body composition was calculated based on detailed measures of skinfold thickness (triceps, subscapular, chest, supra iliac, abdominal, thigh and leg and the circumference of waist, hip, arm, chest, thigh) and legs - a method that is, assuming it is done correctly, as accurate as an expensive DXA-scan (Eston. 2005; Steinberger. 2005).

Figure 1: Relative changes in BMI, fat free mass (FFM), fat mass (FM) and waist circumference over the 6 week study; absolute changes in kg/m², kg and cm are displayed as first number below the bars (Panissa. 2016).

As you can see in Figure 1, both interval and steady state training induced significant pre- to post-decreases for fat mass, fat percentage, waist circumference and sum of seven skinfolds.

This is no "HIIT is better than LISS / MICT study! Theoretically, the study at hand "proves" that HIIT is more effective than LISS, but let's be honest: if you volume-equate HIIT and light / medium intensity training you end up at durations for the LISS / MICT of which no one would be surprised that they don't trigger fat loss. Plus: Facebook Fans know: HIIT decreases MICT / LISS increases appetite when all things are considered (more). Furthermore, the women were untrained and didn't do extra resistance training which would add additional load on the sympathetic nervous system and may thus (if done 3+ times per week) better be combined with LISS or MICT which would provide a parasympathetic stimulus that could ideally complement your resistance training training.

With a 2:1 fat to muscle ratio, the HIIT regimen was yet significantly more successful in improving the subjects' body composition (which obviously depends on the relative, not the total amount of fat) and that despite the fact that the energy intake didn't change significantly in either of the groups.

Figure 2: Daily energy intake in kcal before and during / after the exercise intervention (Panissa. 2016).

Another parameter that showed a measurable, albeit not significant inter-group difference is the effect of the exercise intervention on the subjects' fitness, as it can be predicted based on the subjects VO2max, a value that increased by a whopping 31.12% in the HIIT group, and only 16.70% in the MICT group - a difference that can hardly surprise the average SuppVersity reader.

Isn't HIIT for everyone? Study suggests: Effective- and usefulness of high intensity interval training depend on age and fitness level | learn more

Bottom line: HIIT wins, but not with a statistically significant advantage. As the authors point out, "the main result of the present study was that although the HIIT was able to promote a higher decrease in body fat mass" (Panissa. 2016). Furthermore, the observed benefits of HIIT were not, as previous studies had suggested, due to changes in hunger and energy intake. This important observation leads the authors to conclude that "the hypothesis that changes in hunger (measured by analogical visual scale in all training sessions) and in energy intake (measured by food diaries preand post-training) would contribute to a higher efficiency of HIIT to decrease body fat was not confirmed by our results" (Panissa. 2014).

What the scientists forget to mention in said conclusion, however, is that the lack of statistical significant differences may be a consequence of the "short term" nature of their study, they emphasized in the title "Can short-term high-intensity intermittent training reduce adiposity?" (Panissa. 2016). I bet: In a longer term and/or better powered follow up study, the already visible changes will achieve statistical significance | Comment!

References:

• Edwards S. "High performance training and racing." In: Edwards S (ed) High performance training and racing. Feet Fleet Press (2013), Sacramento, pp 113–12.
• Eston, R. G., et al. "Prediction of DXA-determined whole body fat from skinfolds: importance of including skinfolds from the thigh and calf in young, healthy men and women." European journal of clinical nutrition 59.5 (2005): 695-702.
• Panissa, Valéria Leme Gonçalves, et al. "Can short-term high-intensity intermittent training reduce adiposity?." Sport Sciences for Health (2016): 1-6.
• Steinberger, J., et al. "Comparison of body fatness measurements by BMI and skinfolds vs dual energy X-ray absorptiometry and their relation to cardiovascular risk factors in adolescents." International journal of obesity 29.11 (2005): 1346-1352.
• Subar, Amy F., et al. "Assessment of the accuracy of portion size reports using computer-based food photographs aids in the development of an automated self-administered 24-hour recall." Journal of the American Dietetic Association 110.1 (2010): 55-64.

Carbohydrate Timing Boosts Training Effect: Cut Out Carbs After PM Glycogen Depleting HIT Workout ⇨ "Sleep Low" to Make Game-Changing Performance Gains in Only 3 Weeks

Carbohydrate Timing Boosts Training Effect: Cut Out Carbs After PM Glycogen Depleting HIT Workout ⇨ "Sleep Low" to Make Game-Changing Performance Gains in Only 3 Weeks

athletes carbohydrate timing CHO glycogen glycogen depletion high carbohydrate HIIT hit LISS LIT low carbohydrate performance triathlon

You are no triathlete or coach? That doesn't mean that this study isn't of interest for you. The figurative "extra wind" this training strategy can give you is relevant for almost every athlete.

In a recent study, scientists from the French National Institute of Sport investigated the effect of a chronic dietary periodization strategy in a group of twenty-one highly-trained male triathletes. Previous studies, in which "train-low" strategies, during which athletes are deliberately carbohydrate restricted over certain periods of their training cycle, have reported robust a up-regulation of selected markers of training adaptation (increased whole body fat oxidation, increased activities of oxidative enzymes) compared to training with normal glycogen stores and high CHO availability, however, the subjects experienced at best disappointing performance increases.

Learn more about building muscle and strength at www.suppversity.com

Acutely Increased Hormones Don't Grow Muscle?

Alternating Squat & Blood Pressure - Productive?

Pre-Exhaustion Exhausts Your Growth Potential

Exercise not Intensity Variation for Max. Gains

Battle the Rope to Get Ripped & Strong

Study Indicates Cut the Volume Make the Gains!

Scientists have long speculated that the disconnect between the benefits "training low" offers on the level of cellular / mitochondrial adaptation, on the one hand, and the real-world performance increases, on the other hand, could be a consequence of the necessarily reduced high intensity training intensity during the low-carb phases (Yeo. 2008; Hulston. 2010). If we simply assume that this hypothesis is correct, the solution to the problem should be obvious: Train low when carbohydrates are not necessary and use them, whenever they promote maximal performance.

Marquet et al. implemented this principle in a way I tried to illustrated in Figure 1. More specifically, they tried to maximize the subjects' performance during PM high-intensity training (HIT) by providing copious amounts of carbohydrates before the session and restricted the carbohydrate intake to close to zero after this glycogen-depleting workout.To test the efficacy of this protocol, the scientists used a 2x3 week study design in which the first 3 weeks were used to standardize the volunteers training regimen (10-15 h·wk- 1 : 40% running, 35% cycling, 25% swimming), assess subjects' compliance to the study demands and ensure they all attained similar baseline fitness measures before study commencement.

Figure 1: Overview of important aspects of the dietary / supplemental aspects of the study.

During the decisive second 3-week phase, the subjects were instructed to follow identical diets (by prescribing exact menus, the scientists achieved a high degree of standardization) in combination with either the previously described "sleep low" carbohydrate intake strategy or their usual carbohydrate intake patterns. Unlike the diet / supplementation regimen, the training program the subjects followed was identical for all of them - it ...

Figure 2: Sample weekly protocol for training and CHO intake (g/kg) to achieve different CHO avail. around training (Marquet. 2016)

"consisted of six sessions over four consecutive days, including high intensity training (HIT) sessions in the afternoon and low intensity training (LIT) sessions the next morning. [...] LIT sessions consisted in 60 min cycling at 65% MAP (218.8 ± 20.4 W - 95% CI: 227.5 and 210.7), while HIT sessions consisted alternatively in 8 x 5 min cycling at 85% MAP (286 ± 26.7 W- 95% CI: 297.5 and 274.7) or 6x5 min running at their individual 10 km intensity with 1 min recovery between sets (37). [...] One LIT session per day was prescribed for the other days of the week for a total training volume of 10-15 h" (Marquet. 2016).

All subjects used their own training equipment to record their activity, the duration and intensity of exercise and heart rate. In conjunction with the volunteers' perceived exertion records, as well as VO2max tests, maximal and submaximal performance tests and the results of a simulation of the final leg of a triathlon race, the scientists got a pretty comprehensive set of data.

The effect of "training low" largely depends on the master regulator of mitochondrial adaptation PGC-1a. The latter is activated not just by the contraction induced calcium flux and exercise stress, but also by a lack of glycogen and increased levels of the (low) energy sensing protein AMPK.

How does "training low" work? By deliberately restricting the carbohydrate intake during certain phases of your training you will be able to train in a glyocogen-depleted state and thus with clearly suboptimal fuel availability. The lack of readily available glucose that can be derived from the glycogen stores in your muscle, whenever necessary, exerts profound effects on your overall resting fuel metabolism and patterns of fuel utilization during exercise and triggers acute regulatory processes underlying enzyme and gene expression, as well as cell signaling (signaling proteins, gene expression, transcription rate of several genes, enzymes activity) which regulate the adaptive response to exercise. The results are an increased capacity to oxidize fat, a reduced reliance on glucose as a preferred substrate, etc.

Data that tells us that the authors' hypothesis that they could get the benefits of training low while avoiding the negative sides by "sleeping low" was accurate:

• 

  Figure 3: Make no mistake about it! The total amount of CHO the subjects consumed was identical it was just timed differently. No difference existed for any of the other macronutrients, either (Marquet. 2016).

  There was a significant improvement in delta efficiency during submaximal cycling , i.e. the power output per calorie, a very important measure for endurance athletes, for the "sleep low" compared to the control group (CON: +1.4 ± 9.3 %, SL: +11 ± 15 %, P<0.05).
• A similarly pronounced, albeit due to inter-individual differences, which loom large in studies with relatively few participants, only borderline significant (P = 0.06) beneficial effect was observed during the supra-maximal cycling to exhaustion trial at 150% of peak aerobic power, where the control group saw improve-ments of only 1.63 ± 12.4 %, while the "sleep low" group improved by 12.5 ± 19.0 %.
• The "sleep low" protocol also triggered significantly higher (P < 0.05) improvements in 10k running performance, where the meager -0.10 ± 2.03 % increase in the control group was topped by a -2.9 ± 2.15 % performance increase in the "sleep low" group.

In the "sleep low" group, even the effects on the body composition were significantly more pronounced compared to the control group. To be precise, the subjects who "slept low" burned a whopping 8.7 ± 7.4 % body fat literally overnight, while the control group lost a likewise measurable, but significantly lower and overall non-significant -2.6 ± 7.4% of their body fat - don't be mislead by the size of the bars in Figure 4; the fat mass is on the right axis which starts at 8kg and ends at 10kg. So there was no significant inter-group difference at baseline. No significant inter-group differences were observed for the changes in lean and total mass, either.

Figure 4: Even if you're not training for performance, the improvements in body composition, or more specifically the significant reduction in body fat without sign. changes in lean or total mass, may be of interest for you | total and lean mass on the left axis, fat mass on the right axis; all values in kilograms; sign. changes in % above bars (Marquet. 2016).

Against that background, it is by no means an exaggeration to say that even in the short-term (and that's what I consider particularly impressive here) the "periodization of dietary CHO availability around selected training sessions" can promote "significant improvements" in several highly relevant performance marker of trained athletes" (Marquet. 2016).

8x Increase in "Mitochondria Building" Protein PGC1-Alpha W/ Medium Inten-sity Exercise in Glycogen Depleted Elite(!) Cyclists | Learn more

Drop the carbs pre-bed! No, that's not because carbohydrates in the evening would make you fat. As a SuppVersity reader you know that this is bogus (learn more). The reason why you should consider dropping carbs in the PM (or rather after intense workouts) is their "anti-adaptive" effect - an effect that occurs in response to their ability to replenish your glycogen-stores and thus shut down the "we need to adapt to use more fat" signal to your mitochondria...

Ok, that's not exactly the most scientific explanation (see red box for more), but it is one that highlights one of the most important and yet commonly overlooked principles of physiological adaptations: they occur in response to a need.

If you always provide more than enough carbohydrates, there's no need to increase your ability to use fat as a fuel. If, on the other hand, you (A) fuel yourself with carbs when your body really needs them (during HIT training) to perform at the crucial i + 1 level that will trigger an adaptive response at high intensities, and (B) cut yourself off of a readily available carbohydrate supply when you don't need them (during sleep and low intensity exercise) you maximize the adaptive response to both HIT and LIT (low intensity training) and boost your overall training results | Comment!

References:

• Hulston, Carl J., et al. "Training with low muscle glycogen enhances fat metabolism in well-trained cyclists." Medicine and science in sports and exercise 42 (2010): 2046-55.
• Marquet, et al. "Enhanced Endurance Performance by Periodization of CHO Intake: “Sleep Low” Strategy." Medicine & Science in Sports & Exercise (2015): Publish Ahead of Print.
• Yeo, Wee Kian, et al. "Skeletal muscle adaptation and performance responses to once a day versus twice every second day endurance training regimens." Journal of Applied Physiology 105.5 (2008): 1462-1470.