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The effects of a calcium-rich pre-exercise meal on biomarkers of calcium homeostasis in competitive female cyclists: a randomised crossover trial.

Haakonssen EC, Ross ML, Knight EJ, Cato LE, Nana A, Wluka AE, Cicuttini FM, Wang BH, Jenkins DG, Burke LM - PLoS ONE (2015)

Bottom Line: PTH was 1.55 [1.20, 2.01] times lower in CAL immediately post-exercise and 1.45 [1.12, 1.88] times lower at 40 min post-exercise.CTX-I was 1.40 [1.15, 1.70] times lower in CAL at immediately post-exercise, 1.30 [1.07, 1.57] times lower at 40 min post-exercise and 1.22 [1.00, 1.48] times lower at 190 min post-exercise (p < 0.05).There was no significant interaction between pre-exercise meal condition and time point for CTX-II (p = 0.732) or PINP (p = 0.819).

View Article: PubMed Central - PubMed

Affiliation: Sports Nutrition, Australian Institute of Sport, Belconnen, 2616, Australia; Physiology, Australian Institute of Sport, Belconnen, 2616, Australia; Human Movement Studies, University of Queensland, St Lucia, 4072, Australia.

ABSTRACT

Purpose: To examine whether a calcium-rich pre-exercise meal attenuates exercise-induced perturbations of bone calcium homeostasis caused by maintenance of sweat calcium losses.

Methods: Using a randomized, counterbalanced crossover design, 32 well-trained female cyclists completed two 90 min cycling trials separated by 1 day. Exercise trials were preceded 2 hours by either a calcium-rich (1352 ± 53 mg calcium) dairy based meal (CAL) or a control meal (CON; 46 ± 7 mg calcium). Blood was sampled pre-trial; pre-exercise; and immediately, 40 min, 100 min and 190 min post-exercise. Blood was analysed for ionized calcium and biomarkers of bone resorption (Cross Linked C-Telopeptide of Type I Collagen (CTX-I), Cross Linked C-Telopeptide of Type II Collagen (CTX-II), Parathyroid Hormone (PTH), and bone formation (Procollagen I N-Terminal Propeptide (PINP)) using the established enzyme-linked immunosorbent assay technique.

Results: PTH and CTX-I increased from pre-exercise to post-exercise in both conditions but was attenuated in CAL (p < 0.001). PTH was 1.55 [1.20, 2.01] times lower in CAL immediately post-exercise and 1.45 [1.12, 1.88] times lower at 40 min post-exercise. CTX-I was 1.40 [1.15, 1.70] times lower in CAL at immediately post-exercise, 1.30 [1.07, 1.57] times lower at 40 min post-exercise and 1.22 [1.00, 1.48] times lower at 190 min post-exercise (p < 0.05). There was no significant interaction between pre-exercise meal condition and time point for CTX-II (p = 0.732) or PINP (p = 0.819).

Conclusion: This study showed that a calcium-rich pre-exercise breakfast meal containing ~1350 mg of calcium consumed ~90 min before a prolonged and high intensity bout of stationary cycling attenuates the exercise induced rise in markers of bone resorption--PTH and CTX-I.

Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12614000675628.

No MeSH data available.


Related in: MedlinePlus

Serum concentrations of biomarkers for bone turn over, calcium homeostasis and haematocrit before and after control (CON) and calcium-rich (CAL) meal conditions and exercise.Mean ± 95% CI Haematocrit (Hct; A); ionized cacium (iCa: B); and concentrations of parathyroid hormone (PTH: C); cross linked C-telopeptide of type I collagen (CTX-I: D); cross linked C-telopeptide of type II collagen (CTX-II: E); procollagen I N-terminal propeptide (PINP: F); and at each time point for control (CON: open circles) and calcium (CAL: solid squares) trials. Blood samples were taken pre-trial at T = -15 min; pre-exercise at T = 115 min; and post-exercise at all subsequent time points. *Significant difference (p < 0.05) between trial meal conditions at the indicated time point
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pone.0123302.g003: Serum concentrations of biomarkers for bone turn over, calcium homeostasis and haematocrit before and after control (CON) and calcium-rich (CAL) meal conditions and exercise.Mean ± 95% CI Haematocrit (Hct; A); ionized cacium (iCa: B); and concentrations of parathyroid hormone (PTH: C); cross linked C-telopeptide of type I collagen (CTX-I: D); cross linked C-telopeptide of type II collagen (CTX-II: E); procollagen I N-terminal propeptide (PINP: F); and at each time point for control (CON: open circles) and calcium (CAL: solid squares) trials. Blood samples were taken pre-trial at T = -15 min; pre-exercise at T = 115 min; and post-exercise at all subsequent time points. *Significant difference (p < 0.05) between trial meal conditions at the indicated time point

Mentions: All 32 cyclists completed both trials. Results for Hct, iCa, PTH, CTX-I, CTX-II, and PINP are shown in Fig 3 and S2 Table. There was no interaction between pre-trial meal and time for Hct (F5, 310 = 1.105; p = 0.36), so this interaction was dropped from the model. There were main effects for time (F5, 310 = 75.41; p < 0.01) with Hct increasing on average 2.6 percentage units [1.8, 3.4] from T = 115 min (pre-exercise) to T = 210 min (post-exercise). There were also main effects for pre-trial meal (F5, 310 = 75.41; p < 0.01) with Hct being on average higher in CON (41.4% [40.6, 42.2]) than CAL (40.8% [40.1, 41.6]).


The effects of a calcium-rich pre-exercise meal on biomarkers of calcium homeostasis in competitive female cyclists: a randomised crossover trial.

Haakonssen EC, Ross ML, Knight EJ, Cato LE, Nana A, Wluka AE, Cicuttini FM, Wang BH, Jenkins DG, Burke LM - PLoS ONE (2015)

Serum concentrations of biomarkers for bone turn over, calcium homeostasis and haematocrit before and after control (CON) and calcium-rich (CAL) meal conditions and exercise.Mean ± 95% CI Haematocrit (Hct; A); ionized cacium (iCa: B); and concentrations of parathyroid hormone (PTH: C); cross linked C-telopeptide of type I collagen (CTX-I: D); cross linked C-telopeptide of type II collagen (CTX-II: E); procollagen I N-terminal propeptide (PINP: F); and at each time point for control (CON: open circles) and calcium (CAL: solid squares) trials. Blood samples were taken pre-trial at T = -15 min; pre-exercise at T = 115 min; and post-exercise at all subsequent time points. *Significant difference (p < 0.05) between trial meal conditions at the indicated time point
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4430171&req=5

pone.0123302.g003: Serum concentrations of biomarkers for bone turn over, calcium homeostasis and haematocrit before and after control (CON) and calcium-rich (CAL) meal conditions and exercise.Mean ± 95% CI Haematocrit (Hct; A); ionized cacium (iCa: B); and concentrations of parathyroid hormone (PTH: C); cross linked C-telopeptide of type I collagen (CTX-I: D); cross linked C-telopeptide of type II collagen (CTX-II: E); procollagen I N-terminal propeptide (PINP: F); and at each time point for control (CON: open circles) and calcium (CAL: solid squares) trials. Blood samples were taken pre-trial at T = -15 min; pre-exercise at T = 115 min; and post-exercise at all subsequent time points. *Significant difference (p < 0.05) between trial meal conditions at the indicated time point
Mentions: All 32 cyclists completed both trials. Results for Hct, iCa, PTH, CTX-I, CTX-II, and PINP are shown in Fig 3 and S2 Table. There was no interaction between pre-trial meal and time for Hct (F5, 310 = 1.105; p = 0.36), so this interaction was dropped from the model. There were main effects for time (F5, 310 = 75.41; p < 0.01) with Hct increasing on average 2.6 percentage units [1.8, 3.4] from T = 115 min (pre-exercise) to T = 210 min (post-exercise). There were also main effects for pre-trial meal (F5, 310 = 75.41; p < 0.01) with Hct being on average higher in CON (41.4% [40.6, 42.2]) than CAL (40.8% [40.1, 41.6]).

Bottom Line: PTH was 1.55 [1.20, 2.01] times lower in CAL immediately post-exercise and 1.45 [1.12, 1.88] times lower at 40 min post-exercise.CTX-I was 1.40 [1.15, 1.70] times lower in CAL at immediately post-exercise, 1.30 [1.07, 1.57] times lower at 40 min post-exercise and 1.22 [1.00, 1.48] times lower at 190 min post-exercise (p < 0.05).There was no significant interaction between pre-exercise meal condition and time point for CTX-II (p = 0.732) or PINP (p = 0.819).

View Article: PubMed Central - PubMed

Affiliation: Sports Nutrition, Australian Institute of Sport, Belconnen, 2616, Australia; Physiology, Australian Institute of Sport, Belconnen, 2616, Australia; Human Movement Studies, University of Queensland, St Lucia, 4072, Australia.

ABSTRACT

Purpose: To examine whether a calcium-rich pre-exercise meal attenuates exercise-induced perturbations of bone calcium homeostasis caused by maintenance of sweat calcium losses.

Methods: Using a randomized, counterbalanced crossover design, 32 well-trained female cyclists completed two 90 min cycling trials separated by 1 day. Exercise trials were preceded 2 hours by either a calcium-rich (1352 ± 53 mg calcium) dairy based meal (CAL) or a control meal (CON; 46 ± 7 mg calcium). Blood was sampled pre-trial; pre-exercise; and immediately, 40 min, 100 min and 190 min post-exercise. Blood was analysed for ionized calcium and biomarkers of bone resorption (Cross Linked C-Telopeptide of Type I Collagen (CTX-I), Cross Linked C-Telopeptide of Type II Collagen (CTX-II), Parathyroid Hormone (PTH), and bone formation (Procollagen I N-Terminal Propeptide (PINP)) using the established enzyme-linked immunosorbent assay technique.

Results: PTH and CTX-I increased from pre-exercise to post-exercise in both conditions but was attenuated in CAL (p < 0.001). PTH was 1.55 [1.20, 2.01] times lower in CAL immediately post-exercise and 1.45 [1.12, 1.88] times lower at 40 min post-exercise. CTX-I was 1.40 [1.15, 1.70] times lower in CAL at immediately post-exercise, 1.30 [1.07, 1.57] times lower at 40 min post-exercise and 1.22 [1.00, 1.48] times lower at 190 min post-exercise (p < 0.05). There was no significant interaction between pre-exercise meal condition and time point for CTX-II (p = 0.732) or PINP (p = 0.819).

Conclusion: This study showed that a calcium-rich pre-exercise breakfast meal containing ~1350 mg of calcium consumed ~90 min before a prolonged and high intensity bout of stationary cycling attenuates the exercise induced rise in markers of bone resorption--PTH and CTX-I.

Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12614000675628.

No MeSH data available.


Related in: MedlinePlus