Table 3

Cardiac MRI parameters at rest and during submaximal exercise at baseline and after 20 weeks (posttraining) in adolescents with type 1 diabetes who trained (T1D Tx), with type 1 diabetes who did not train (T1D Con), and without diabetes who trained (ND Tx)

TimeBaselinePosttraining
T1D ConT1D TxND TxT1D ConT1D TxND Tx
N (% female)15 (53)38 (47)22 (55)13 (46)37 (49)22 (55)
Left ventricular mass (g)At rest129.5 ± 4.8128.4 ± 3.1133.7 ± 4.3130.8 ± 5.2131.6 ± 3.2###141.7 ± 4.4####
Left ventricular mass (g/kg FFM)2.59 (2.39–2.78)2.58 (2.45–2.70)2.72 (2.55–2.88)2.58 (2.39–2.77)2.60 (2.49–2.71)2.77 (2.62–2.92)
Heart rate (bpm)At rest72.9 (67.4–78.5)75.2 (71.7–78.7)70.1 (65.3–74.8)73.7 (67.6–79.8)69.8 (66.2–73.5)##65.0 (60.1–69.8)#
Submaximal exercise109.4 (106.6–112.3)109.8 (108.0–111.6)108.9 (106.5–111.4)108.3 (106.0–110.6)108.2 (106.8–109.6)##107.9 (106.0–109.7)
Systolic blood pressure (mmHg)At rest108.2 (103.0–113.3)110.4 (107.1–113.6)**102.7 (98.3–107.1)109.6 (104.4–114.8)107.9 (104.7–111.0)102.9 (98.7–107.1)
Submaximal exercise128.2 (119.8–136.6)128.2 (123.0–133.5)119.3 (112.1–126.5)123.5 (115.8–131.1)123.0 (118.4–127.6)#119.3 (113.2–125.4)
Diastolic blood pressure (mmHg)At rest60.3 (56.2–64.5)60.7 (58.1–63.3)*56.0 (52.4–59.5)60.8 (56.7–64.8)56.4 (53.9–58.8)##58.0 (54.8–61.3)
Submaximal exercise66.2 (60.8–71.5)65.9 (62.6–69.3)60.7 (56.2–65.3)66.1 (61.4–70.8)64.7 (61.9–67.5)60.8 (57.0–64.5)
Mean arterial pressure (mmHg)At rest76.3 (72.7–79.9)*77.2 (75.0–79.5)**71.5 (68.5–74.6)77.0 (73.5–80.6)73.5 (71.4–75.7)##73.0 (70.1–75.8)
Submaximal exercise86.8 (81.4–92.2)86.7 (83.3–90.1)80.3 (75.6–84.9)85.2 (80.5–89.9)84.1 (81.3–86.9)80.3 (76.5–54.1)
Cardiac output (L/min)At rest6.66 (6.04–7.27)7.00 (6.61–7.39)6.67 (6.13–7.22)6.62 (5.87–7.36)7.02 (6.56–7.48)6.65 (6.03–7.27)
Submaximal exercise10.25 (9.49–11.00)*10.30 (9.82–10.79)**11.45 (10.78–12.12)10.03 (9.08–10.98)***11.40 (10.81–11.99)*,,####12.56 (11.76–13.35)##
Cardiac output (mL/kg FFM)At rest133.5 (118.8–146.3)141.0 (132.3–149.6)142.3 (130.6–154.1)130.4 (116.0–144.7)137.9 (129.2–146.5)134.8 (123.3–146.3)
Submaximal exercise206.5 (190.8–222.1)**207.7 (197.8–217.5)**235.9 (222.5–249.3)198.2 (180.4–216)****225.8 (215.1–236.6)**,††,###252.4 (238.0–266.7)##
Stroke volume (mL)At rest91.9 (84.7–99.1)92.9 (88.3–97.5)96.3 (89.9–102.7)91.2 (82.4–99.9)*100.5 (95.1–105.9)####104.9 (97.6–112.2)##
Submaximal exercise93.9 (87.1–100.7)*93.7 (89.4–98.0)**105.9 (99.9–111.9)92.8 (84.0–101.6)***105.5 (100.1 –110.9)*,,####116.7 (109.3–124.0)##
Stroke volume (mL/kg FFM)At rest1.82 (1.67–1.98)*1.87 (1.77–1.97)*2.05 (1.92–2.19)1.80 (1.64–1.96)**1.98 (1.89–2.08)*,###2.08 (1.95–2.21)
Submaximal exercise1.89 (1.76–2.03)**1.90 (1.82–1.99)***2.17 (2.05–2.28)1.83 (1.67–1.99)****2.09 (1.99–2.19)**,††,####2.34 (2.21–2.47)###
End-diastolic volume (mL)At rest143 (133–153)147 (141–154)157 (148–166)150 (138–162)150 (143–157)#163 (153–173)#
Submaximal exercise135 (126–145)*139 (133–145)*153 (144–161)138 (126–149)**147 (140–154)*,##161 (151–171)#
End-diastolic volume (mL/kg FFM)At rest2.88 (2.67–3.08)*2.96 (2.84–3.09)*3.20 (3.03–3.38)2.97 (2.75–3.18)2.98 (2.85–3.11)*3.21 (3.04–3.39)
Submaximal exercise2.73 (2.54–2.92)**2.81 (2.69–2.93)**3.09 (2.93–3.25)2.72 (2.51–2.92)***2.93 (2.81–3.05)*,#3.18 (3.02–3.34)
End-systolic volume (mL)At rest51.5 (46.3–56.6)*54.3 (51.0–57.6)*60.4 (55.9–65.0)55.7 (49.7–61.8)#50.2 (46.5–54.0)*58.0 (53.0–63.0)
Submaximal exercise41.2 (35.6–46.7)45.2 (41.7–48.8)46.5 (41.6–51.4)44.2 (38.6–49.7)40.1 (36.6–43.6)#43.6 (39.0–48.3)
End-systolic volume (mL/kg FFM)At rest1.04 (0.94–1.14)*1.09 (1.03–1.16)*1.21 (1.12–1.30)1.11 (0.99–1.23)1.00 (0.93–1.07)*,##1.13 (1.04–1.23)#
Submaximal exercise0.83 (0.72–0.94)0.92 (0.85–0.98)0.91 (0.82–1.01)0.88 (0.76–0.99)0.81 (0.74–0.87)##0.85 (0.76–0.94)##
Ejection fraction (%)At rest64.4 (61.9–66.9)63.0 (61.4–64.5)62.8 (60.6–64.9)61.8 (59.2–64.4)##66.3 (64.8–67.9)††,###64.7 (62.6–66.8)
Submaximal exercise69.4 (64.7–74.1)66.1 (63.2–69.1)69.9 (65.9–73.9)67.5 (64.7–70.4)**,#72.1 (70.4–73.8)††,####73.4 (71.1–75.6)###
Stroke workAt rest95.2 (86.4–104.0)97.6 (92.0–103.3)94.4 (86.6–102.2)95.5 (84.5–106.5)101.0 (94.2–107.8)104.6 (95.5–113.8)##
Submaximal exercise111.5 (99.4–123.5)110.5 (102.8–118.2)118.8 (108.2–129.4)108.1 (96.4–119.9)*120.5 (113.2–127.7)##128.5 (118.7–138.3)#
Total peripheral resistanceAt rest11.9 (10.7–13.0)11.5 (10.7–12.2)11.0 (10.0–12.0)12.1 (11.0–13.1)11.1 (10.4–11.7)11.4 (10.5–12.3)
Submaximal exercise8.5 (7.8–9.4)*8.7 (8.2–9.2)**7.2 (6.5–7.9)8.8 (8.0–9.5)****7.6 (7.2–8.1)*,,####6.6 (5.9–7.2)
Workload (watts)Submaximal exercise37.7 (30.7–44.7)35.4 (31.2–39.6)34.9 (28.7–41.1)32.5 (25.0–40.1)*41.5 (37.1–45.8)**,,#49.0 (42.8–55.2)####
  • Data are means and 95% CIs adjusted for age and sex.

  • FFM, fat-free mass.

  • *P < 0.05;

  • **P < 0.01;

  • ***P < 0.001;

  • ****P < 0.0001 for comparisons with ND Tx.

  • P < 0.05;

  • ††P < 0.01 for comparisons between the two groups with diabetes.

  • #P < 0.05;

  • ##P < 0.01;

  • ###P < 0.001;

  • ####P < 0.0001 for a change from baseline within group.