Acute Effect of Popular High-Intensity Functional Training Exercise on Physiologic Markers of Growth

Abstract

Kliszczewicz, B, Markert, CD, Bechke, E, Williamson, C, Clemons, KN, Snarr, RL, and McKenzie, MJ. Acute effect of popular high-intensity functional training exercise on physiologic markers of growth. J Strength Cond Res 35(6): 1677–1684, 2021—Constantly evolving, high-intensity functional training (HIFT) exercise consists of various modalities, orders, weights, and repetition schemes. High-intensity functional training has gained popularity among the general population, but lacks empirical evidence regarding acute adaptive responses. The purpose of this study was to describe the acute effects of 2 representative bouts of HIFT on physiologic markers of growth. For convenience, the bouts are designated “short” (<5 minutes) and “long” (∼15 minutes), although duration was not the only difference between bouts. Ten apparently healthy men (28.1 ± 5 years) performed 2 HIFT bouts in a randomized crossover design. Blood was collected at 5 time points (Pre, Post, 1, 3, and 6 hours) to examine growth hormone (GH), insulin-like growth factor (IGF-1), insulin-like growth factor binding proteins 1 and 2 (IGFBP-1 and IGFBP-2), and vascular endothelial growth factor (VEGF). Blood lactate concentration ([La]) was analyzed at the Pre and Post time points. A repeated-measures analysis of variance (ANOVA) revealed no trial differences among the markers (IGF-1, IGFBP-1, IGFBP-2, and VEGF) except GH at Post, where the long bout produced a greater effect (p = 0.005). Mean GH levels (pg·ml−1) in the short bout increased from 68.4 to 106.5, and in the long bout, mean GH levels increased from 38.5 to 286.4. The repeated-measures ANOVA revealed a main time effect in GH (p = 0.037), while a post hoc t-test demonstrated elevated GH at 1 hour (p = 0.018) when compared with Pre. No time-dependent change (p > 0.05) was observed in IGF-1, IGFBP-1, IGFBP-2, or VEGF. Mean blood [lactate] increased more than tenfold in both bouts. The findings of this descriptive study suggest that, other than GH, there are no acute differences in markers of skeletal muscle or vascular growth between these 2 specific HIFT bouts.

Characterization of Hormonal, Metabolic, and Inflammatory Responses in CrossFit® Training: A Systematic Review

“…In the study by Kliszczewicz et al ( 2018a ), GH was higher 1 h after training involving CV and weightlifting exercises compared with weightlifting exercises only. Like testosterone, when compared between different groups, GH was higher in healthy men than in inactive men (Cadegiani et al, 2019 ).…”

“…The training intensity was verified in a few studies through heart rate (HR) assessment, in which the HR remained between 85.9 and 97.4% of the maximum HR (Fernandez-Fernandez et al, 2015 ; Murawska-Cialowicz et al, 2015 ; Kliszczewicz et al, 2018a , b ; Maté-Muñoz et al, 2018 ; Tibana et al, 2018 ; Ahmad et al, 2019 ; Feito et al, 2019a ). Regarding the WOD time, 10 studies used protocols with times <10 min (Fernandez-Fernandez et al, 2015 ; Kliszczewicz et al, 2017 , 2018a , b ; Maté-Muñoz et al, 2017 , 2018 ; Mangine et al, 2018 , 2019 ; Tibana et al, 2018 ; Timón et al, 2019 ), 13 studies used protocols with times between 10 and 19 min (Murawska-Cialowicz et al, 2015 ; Shaw et al, 2015 ; Escobar et al, 2016 , 2017 ; Kliszczewicz et al, 2017 , 2018a , b ; Maté-Muñoz et al, 2017 ; Durkalec-Michalski et al, 2018 ; Mangine et al, 2018 , 2019 ; Tibana et al, 2018 ; Feito et al, 2019a ), and five studies used protocols with times over 20 min (Fernandez-Fernandez et al, 2015 ; Maté-Muñoz et al, 2017 , 2018 ; Mangine et al, 2018 ; Tibana et al, 2019b ).…”

“…The studies that described the training protocols analyzed participants who performed different combinations of multiple types of exercise modalities. CV, gymnastic and weightlifting exercises): gymnastic ( n = 2; Shaw et al, 2015 ; Ahmad et al, 2019 ), G + W ( n = 4; Fernandez-Fernandez et al, 2015 ; Escobar et al, 2016 , 2017 ; Timón et al, 2019 ), CV + weightlifting ( n = 6; Perciavalle et al, 2016 ; Kliszczewicz et al, 2017 , 2018a , b ; Coco et al, 2019 ; Feito et al, 2019a ), and CV + gymnastic + weightlifting ( n = 9; Tibana et al, 2016 , 2018 , 2019a , b ; Maté-Muñoz et al, 2017 , 2018 ; Durkalec-Michalski et al, 2018 ; Mangine et al, 2018 , 2019 ).…”

“…Eight studies (Kliszczewicz et al, 2017 , 2018a , b ; Mangine et al, 2018 , 2019 ; Cadegiani et al, 2019 ; Poderoso et al, 2019 ; Tibana et al, 2019b ) investigated hormonal responses (see Table 1 ). The variables analyzed were testosterone and cortisol (Mangine et al, 2018 ; Cadegiani et al, 2019 ; Poderoso et al, 2019 ; Tibana et al, 2019a ), GH and IGF-1 (Kliszczewicz et al, 2018a ; Cadegiani et al, 2019 ), or adrenaline and noradrenaline (Kliszczewicz et al, 2017 , 2018b ; Cadegiani et al, 2019 ; Mangine et al, 2019 ).…”

“…These responses, which can be induced by stressors and are vital for host defense and natural tissue homeostasis, initiate the elimination of noxious compounds and damaged tissue (Allen et al, 2015 ). Apparently, several hormonal (Kliszczewicz et al, 2018a ; Mangine et al, 2018 ; Cadegiani et al, 2019 ), metabolic (Maté-Muñoz et al, 2018 ; Tibana et al, 2018 ; Feito et al, 2019a ) and inflammatory (Michnik et al, 2017 ; Durkalec-Michalski et al, 2018 ) changes occur with CrossFit ® practice. Emphasizing the strong relationship between the hormonal, metabolic, and inflammatory profiles that occur with systematic practice of this high-intensity activity is important (Coco et al, 2019 ; Tibana et al, 2019b ).…”