OBJECTIVE: To compare the thyroid hormonal responses to high-intensity interval exercise (IE) and steady-state endurance exercise (SEE) in highly trained males (n=15). DESIGN: The IE session consisted of repeated periods of 90-seconds treadmill running at 100-110% VO(2max) and 90-seconds active recovery at 40% VO(2max) for 42-47 minutes. The SEE session was a 45-minute run at 60-65% VO(2max). Total work output was equal for each session. A 45-minute supine rest control session (CON) was also performed. Pre-session (PRE), immediate post-session (POST), and 12-hours post-session (12POST) blood samples were collected and used to determine free (f) T₄, fT₃, reverse (r) T₃, and cortisol levels. RESULTS: All PRE hormone levels were within clinical norms and did not differ significantly between sessions. All POST IE and SEE hormone levels were significantly elevated compared to POST CON (p<0.001). At 12POST, no significant differences between CON and SEE hormonal levels were observed; however, fT₃ was significantly reduced and rT3 was significantly elevated in 12POST IE compared to 12POST SEE and CON (p=0.022). For IE, at 12POST a negative correlation (r(s) = -0.70, p<0.004) was found between fT₃ and rT₃.Also, for IE, a positive correlation (r(s) = 0.74, p<0.002) between cortisol POST and rT₃ 12POST was noted, and a negative correlation (r(s) = -0.72, p<0.003) between cortisol POST and fT₃ 12POST. CONCLUSION: IE results in a suppressed peripheral conversion of T₄ to T₃ implying that a longer recovery period is necessary for hormonal levels to return to normal following IE compared to SEE. These findings are useful in the implementation of training regimens relative to recovery needs and prevention of over-reaching-overtraining.
OBJECTIVE: To compare the thyroid hormonal responses to high-intensity interval exercise (IE) and steady-state endurance exercise (SEE) in highly trained males (n=15). DESIGN: The IE session consisted of repeated periods of 90-seconds treadmill running at 100-110% VO(2max) and 90-seconds active recovery at 40% VO(2max) for 42-47 minutes. The SEE session was a 45-minute run at 60-65% VO(2max). Total work output was equal for each session. A 45-minute supine rest control session (CON) was also performed. Pre-session (PRE), immediate post-session (POST), and 12-hours post-session (12POST) blood samples were collected and used to determine free (f) T₄, fT₃, reverse (r) T₃, and cortisol levels. RESULTS: All PRE hormone levels were within clinical norms and did not differ significantly between sessions. All POST IE and SEE hormone levels were significantly elevated compared to POST CON (p<0.001). At 12POST, no significant differences between CON and SEE hormonal levels were observed; however, fT₃ was significantly reduced and rT3 was significantly elevated in 12POST IE compared to 12POST SEE and CON (p=0.022). For IE, at 12POST a negative correlation (r(s) = -0.70, p<0.004) was found between fT₃ and rT₃.Also, for IE, a positive correlation (r(s) = 0.74, p<0.002) between cortisolPOST and rT₃ 12POST was noted, and a negative correlation (r(s) = -0.72, p<0.003) between cortisolPOST and fT₃ 12POST. CONCLUSION: IE results in a suppressed peripheral conversion of T₄ to T₃ implying that a longer recovery period is necessary for hormonal levels to return to normal following IE compared to SEE. These findings are useful in the implementation of training regimens relative to recovery needs and prevention of over-reaching-overtraining.
Authors: Moritz Schumann; Simon Walker; Mikel Izquierdo; Robert U Newton; William J Kraemer; Keijo Häkkinen Journal: Eur J Appl Physiol Date: 2014-01-17 Impact factor: 3.078
Authors: P Sgrò; M Sansone; A Parisi; A Sartorio; A Sansone; F Romanelli; A Lenzi; L Di Luigi Journal: J Endocrinol Invest Date: 2016-05-26 Impact factor: 4.256
Authors: Francisca M Vera; Juan M Manzaneque; Gabriel A Carranque; Francisco M Rodríguez-Peña; Soledad Sánchez-Montes; María J Blanca Journal: Evid Based Complement Alternat Med Date: 2018-10-16 Impact factor: 2.629