Afterburn?

[pugilist]

Lytter man til folk som Alwyn Cosgrove, lyder det som om den afterburn effekt man får af HIIT gør en kæmpe forskel i ens samlede kalorieregnskab. For nogle år siden (da jeg gik på trænerskolen), var jeg dog til et foredrag med en eller anden "ekspert" fra Team Danmark (har lige glemt hans kvalifikationer ), der mente at det var så lidt, at det ingen rolle ville spille i et evt. vægttab.

Jeg har prøvet at finde noget på området, men synes ikke rigtig der er andet end meninger. Er der nogen der ligger inde med lidt konkret info omkring hvor meget/lidt der er tale om?

[pugilist]

Afterburn? Anyone?

[heliotropen]

Jeg refferere til lidt du måske kan bruge i den her tråd (gør andre osse):

http://www.motion-online.dk/fora/index.php...40433&st=60

Se bla. post nr #79

Styre man sin træning og diæt nogenlunde strict i en periode i forvejen, - er det også et forsøg der er muligt at udføre i en ok udgave selv; - Gør så du i en periode ligger på eller lige under dit ligevægtsindtag (skal være ret stabilt) og kør så en periode med Højintens cardio træning (hvilken du selvfølgelig logger) - registrer massetabet, udregn kcalunderskudet, og fratræk den energi du brugte under aktiviteten. - Lav en lign kontrol periode med en lavintens cardio træning. og vær opmærksom på store fejlkilder. - Dit resultatet afhænger selvfølgelig af mange ting, bla. hvordan dit program ser ud, (hvor hårdt, hvor meget osv.), din fysik, din evne til at presse dig selv, yderligere træning osv. - Men skal jeg give et fuldstænigt løst skud ud fra mine effaringer så rammer du nok ind i en 500-1000 kcal's efter forbrænding forløbende ud over en 36-48 timer på en god omgang høj intens cardio træning af denne type - men det er som sagt, blot et løst skud.

M.V.H

Helio

Edited September 18, 2007 by heliotropen

[mugge]

Hvis dine tal passer helio, så vil det give i retning af 17 kcl pr. times cardio. Det er jo ikke meget. Iså fald er After burn noget overvurderet.

[pugilist]

Hvis dine tal passer helio, så vil det give i retning af 17 kcl pr. times cardio. Det er jo ikke meget. Iså fald er After burn noget overvurderet.

Omvendt er det op til 3000 kcal om ugen hvis man har 3 HIIT træningspas. Det svarer vel til knap ½kg fedt om ugen, hvis alt andet er lige. Det synes jeg da ikke er så skidt.

P.S. Tak for svar helio.

Edited September 18, 2007 by pugilist

[-Elvirus-]

Min dovenskab forbyder mig selv at gå igang med at søge materiale og sortere for at finde relevante referencer, MEN hvis du selv er interesseret. kan du søge på pubmed.com.

Søgeord kan med fordel være: EPOC, post exercise energy consumption, exercise post energy consumption, exercise and afterburn, og den dur. Vælg derefter reviews fanebladet for at få en lidt mindre mængde materiale samt noget lettere tilgængeligt at læse.

God fornøjelse :-)

Edited September 18, 2007 by -Elvirus-

[Diddley]

Her er lidt at starte på, der dog ikke understøtter den optimisme vedr. størrelsen af afterburn, som man nogle gange ser her på MOL.

Effects of exercise intensity and duration on the excess post-exercise oxygen consumption.

LaForgia J, Withers RT, Gore CJ.

School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA. [email protected]

Recovery from a bout of exercise is associated with an elevation in metabolism referred to as the excess post-exercise oxygen consumption (EPOC). A number of investigators in the first half of the last century reported prolonged EPOC durations and that the EPOC was a major component of the thermic effect of activity. It was therefore thought that the EPOC was a major contributor to total daily energy expenditure and hence the maintenance of body mass. Investigations conducted over the last two or three decades have improved the experimental protocols used in the pioneering studies and therefore have more accurately characterized the EPOC. Evidence has accumulated to suggest an exponential relationship between exercise intensity and the magnitude of the EPOC for specific exercise durations. Furthermore, work at exercise intensities >or=50-60% VO2max stimulate a linear increase in EPOC as exercise duration increases. The existence of these relationships with resistance exercise at this stage remains unclear because of the limited number of studies and problems with quantification of work intensity for this type of exercise. Although the more recent studies do not support the extended EPOC durations reported by some of the pioneering investigators, it is now apparent that a prolonged EPOC (3-24 h) may result from an appropriate exercise stimulus (submaximal: >or=50 min at >or=70% VO2max; supramaximal: >or=6 min at >or=105% VO2max). However, even those studies incorporating exercise stimuli resulting in prolonged EPOC durations have identified that the EPOC comprises only 6-15% of the net total oxygen cost of the exercise. But this figure may need to be increased when studies utilizing intermittent work bouts are designed to allow the determination of rest interval EPOCs, which should logically contribute to the EPOC determined following the cessation of the last work bout. Notwithstanding the aforementioned, the earlier research optimism regarding an important role for the EPOC in weight loss is generally unfounded. This is further reinforced by acknowledging that the exercise stimuli required to promote a prolonged EPOC are unlikely to be tolerated by non-athletic individuals. The role of exercise in the maintenance of body mass is therefore predominantly mediated via the cumulative effect of the energy expenditure during the actual exercise.

PMID: 17101527 [PubMed - indexed for MEDLINE]

[Diddley]

Her lidt mere

Resistance training volume and post exercise energy expenditure.

Haddock BL, Wilkin LD.

Department of Kinesiology, California State University, San Bernardino, CA 92407-2397, USA. [email protected]

The main purpose of this study was to determine if increasing the volume of a resistance training program, while keeping the intensity the same would significantly increase the recovery energy expenditure, as measured by the excess post-exercise energy expenditure (EPEE). Fifteen resistance-trained women completed two resistance training protocols. Both protocols consisted of nine exercises performed to volitional fatigue, at the previously determined eight RM. The only difference between the two protocols was the number of sets (1-set or 3-sets). All subjects completed both protocols in a randomized and counterbalanced fashion. Energy expenditure, as determined by oxygen consumption and respiratory exchange ratio (RER), was measured continuously prior to exercise, during the exercise session, and during the entire 120 min of recovery. Fingertip blood lactate concentration was determined at baseline, immediately post-exercise, and every 30 min in recovery. The net energy expenditure during exercise was significantly greater during the 3-set protocol (661.9 +/- 43.9 kj) than the 1-set protocol (234.7 +/- 13.4 kj). However, per minute of exercise, there was no significant difference between the two protocols. During the 120 min of recovery, the net EPEE was not significantly different between the two protocols (93.3 +/- 20.1 kj following the 1-set protocol, and 94.1 +/- 7.1 kj following the 3-set protocol). However, when comparing the EPEE to the number of minutes spent in the exercise session, the 1-set protocol led to a significantly greater energy expenditure in the recovery period (1.0 +/- 0.22 kj/min) than did the 3-set protocol (0.4 +/- 0.03 kj/min). These data indicate that in previously trained women, increasing the volume of resistance training, from 1-set to 3-sets, while keeping the intensity the same will not significantly increase EPEE above what is found in a lower volume of work.

PMID: 16475061 [PubMed - indexed for MEDLINE]

[Diddley]

Her lidt om betydningen af træningens længde

Increased resting energy expenditure after 40 minutes of aerobic but not resistance exercise.

Hunter GR, Byrne NM, Gower BA, Sirikul B, Hills AP.

Human Studies and Nutrition Sciences Departments, Room 205 Education Building, University of Alabama, Birmingham, AL 35294-1250, USA. [email protected]

OBJECTIVE: Resting energy expenditure (REE) is increased 24 hours after high-intensity aerobic exercise lasting 60 minutes, whereas results have been inconsistent after resistance training and aerobic exercise of shorter duration. The objective of the study was to compare the effects of 40 minutes of high-intensity aerobic vs. resistance exercise on REE 19 to 67 hours after exercise. RESEARCH METHODS AND PROCEDURES: REE was compared 19, 43, and 67 hours after 40 minutes of aerobic training (AT; 80% maximum heart rate) or resistance training (RT; 10 repetitions at 80% maximum strength, two sets and eight exercises). Twenty-three black and 22 white women were randomly assigned to AT, RT, or no training (controls). Exercisers trained 25 weeks. REE was measured after a 12-hour fast. RESULTS: There was a significant time x group interaction for REE when adjusted for fat-free mass and fat mass, with post hoc tests revealing that the 50-kcal difference between 19 and 43 hours (1310 +/- 196 to 1260 +/- 161 kcal) and the 34-kcal difference between 19 and 67 hours (1310 +/- 196 to 1276 +/- 168 kcal) were significant for AT. No other differences were found, including RT (19 hours, 1256 +/- 160; 43 hours, 1251 +/- 160; 67 hours, 1268 +/- 188 kcal). Urine norepinephrine increased with training only in AT. After adjusting for fat-free mass, REE Delta between 19 and both 43 and 67 hours was significantly related to urine norepinephrine (r = 0.76, p < 0.01 and 0.68, p < 0.03, respectively). DISCUSSION: Consistent with findings on longer duration AT, these results show that 40 minutes of AT elevates REE for 19 hours in trained black and white women. This elevation did not occur with 40 minutes of RT. Results suggest that differences are, in part, due to increased sympathetic tone.

PMID: 17135619 [PubMed - indexed for MEDLINE]

[Diddley]

Her lidt mere om betydningen af træningens længde

Postexercise oxygen consumption in trained females: effect of exercise duration.

Quinn TJ, Vroman NB, Kertzer R.

University of New Hampshire, Department of Kinesiology, Durham 03824.

Many research studies report the long-lasting elevation of metabolism following exercise. However, little is known regarding the impact of duration and intensity on this phenomenon, particularly in trained women in whom the time of the menstrual cycle has been controlled. This study examined the effects of a constant walking intensity (70% of maximal oxygen uptake (VO2max)) on the treadmill at various levels of duration (20, 40, and 60 min) on 3-h recovery of oxygen uptake (VO2). Eight trained (mean +/- SD) (VO2max = 47.6 +/- 3.2 ml.kg-1.min-1) females (mean age = 30.2 +/- 5.0 yr, mean weight = 58.7 +/- 7.6 kg, mean height = 165.6 +/- 7.0 cm) participated in the study. Subjects reported to the lab for a maximal oxygen consumption test and returned on four additional occasions (control, 20, 40, 60 min) in random fashion. Treadmill speed and grade were established to yield the appropriate intensity for each subject. Following each exercise bout subjects sat quietly for a 3-h time period. Variables measured included VO2, minute ventilation (VE), respiratory exchange ratio (RER), heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and core (rectal) temperature (Tc). Variables were measured each 15 min of recovery. An ANOVA was used to assess differences due to duration. Excess postexercise oxygen consumption (EPOC) was calculated by subtracting the resting VO2 from the absolute VO2 and summing the individual EPOCs during each 3-h postexercise session and comparing these individual values to the preexercise VO2 values. The EPOC was significantly elevated (P < 0.05) in each of the three durations as compared with the control (sitting) and preexercise periods. The total EPOC was significantly higher for the 60-min duration (15.2 l) as compared with either 20-min (8.b l) or 40-min (9.8 l) duration (P < 0.05). This was observed without significant changes in VE, RER, HR, SBP, DBP, or Tc. Additionally, there were no differences during exercise across the three durations in VO2, VE, RER, HR, SBP, DBP, or Tc. These data suggest that exercise duration increases EPOC significantly and that a 60-min duration yields approximately twice the EPOC than either 20 or 40 min.

PMID: 7934767 [PubMed - indexed for MEDLINE]

[Diddley]

Her en interessant sammenligning af EPOC og kalorieforbrug ved træning ved forskellige intensiteter.

Effect of exercise intensity and duration on postexercise energy expenditure.

Sedlock DA, Fissinger JA, Melby CL.

Exercise Physiology Laboratory, Purdue University, West Lafayette, IN 47907.

The purpose of this study was to examine 1) the effect of two exercise intensities of equal caloric output on the magnitude (kcal) and duration of excess postexercise oxygen consumption (EPOC) and 2) the effect of exercise of equal intensity but varying duration on EPOC. Ten trained male triathletes performed three cycle ergometer exercises: high intensity-short duration (HS), low intensity-short duration (LS), and low intensity-long duration (LL). Baseline VO2 was measured for 1 h prior to each exercise condition. Postexercise VO2 was measured continuously until baseline VO2 was achieved. The duration of EPOC was similar for HS (33 +/- 10 min) and LL (28 +/- 14 min), and both were significantly longer (P less than 0.05) than the EPOC following LS (20 +/- 5 min). However, total net caloric expenditure was significantly more (P less than 0.05) for HS (29 +/- 8 kcal) than for either LS (14 +/- 6 kcal) or LL (12 +/- 7 kcal). The exercise conditions used in this study did not produce a prolonged EPOC. However, the exercise intensity was shown to affect both the magnitude and duration of EPOC, whereas the exercise duration affected only the duration of EPOC. Moreover, the duration of EPOC and the subsequent caloric expenditure were not necessarily related. Based on the resulting magnitude of the postexercise energy expenditure, it is possible that EPOC may be of some value for weight control over the long term.

PMID: 2626089 [PubMed - indexed for MEDLINE]