Table 1

Studies concerning bone mass, bone metabolism and cycling participation

Study

Participants

Exercise

Years of cycling training

Study design

Data source

Resultsa

Strength of evidence


Number

Sex

Age


Barry et al. (2007) [47]

CYC (20)

M

22 to 45

Competitive level

2-h exercise bout at 60% to 75% VT

Hormones, calcium

Parathyroid was increased after 2 h of cycling.

B: observational

Barry et al. (2008) [43]

CYC (14)

M

27 to 44

>450 h/year

4.9 ± 2.4

Two groups: HIGH and LOW calcium supplementation over 1-year season

DXA

Both groups decreased BMD over 1 year in total hip and subregions, without differences for HIGH or LOW calcium.

A: RCT

Barry et al. (2011) [39]

CYC and TRI (20)

M

37 ± 7.6

-

6.0 ± 6.5

Different calcium supplementation groups over three 35-km trials

DXA, hormones

30% of participants had LS BMD T-score over -1.0. Calcium supplementation attenuates disruption of parathyroid hormone.

A: RCT

Beshgetoor et al. (2000) [41]

CYC (12); RUN (9); CON (9)

F

49.6 ± 7.9

-

-

18 months follow-up

DXA, calcium intake

Femur BMD maintained in CYC and RUN, decline CON. LS BMD maintained RUN, decline CYC and CON. No relationship between BMD and calcium intake.

B: case-control

Brown et al. (2000) [49]

CYC (32)

M/F

16 to 62

Competitive cycling

>2

Two groups: HIGH FAT and HIGH CARBOHYDRATE intake; 12-week intervention

DXA

No differences in fat or lean accumulation between groups. BMD increased in HIGH FAT group.

A: RCT

Campion et al. (2010) [34]

CYC (30)

CON (30)

M

29 ± 3.4

28 ± 4.5

22 to 25 h/week

<1 h/week

-

Cross-sectional

DXA

CYC lower WB, LS, pelvis, femoral neck, upper and lower limbs than CON

B: case-control

Duncan et al. (2002) [21]

CYC (15)

RUN (15)

SWI (15)

TRI (15)

CON (15)

F

16 to 17

≥8 h/week

≥8 h/week

≥8 h/week

≥8 h/week

<2 h/week

3.1 ± 1.8

Cross-sectional

DXA

CYC lower legs BMD than RUN. No differences with CON.

B: case-control

Duncan et al. (2002) [45]

CYC (10)

RUN (10)

SWI (10)

TRI (10)

CON (10)

F

16 to 17

≥8 h/week

≥8 h/week

≥8 h/week

≥8 h/week

<2 h/week

3.1 ± 1.8

Cross-sectional

MRI, DXA

CYC lower cortical CSA, moment of inertia and mid-femur BMD than RUN. No differences with CON.

B: case-control

Fiore et al. (1996) [36]

CYC (14); CAN (18); CON (28)

M

-

-

-

Cross-sectional

DXA

CYC lower WB, LS and pelvic BMD than CAN. No differences with CON.

B: case-control

Guillaume et al. (2012) [38]

CYC (29)

M

26.5 ± 5.3

25,000 to 30,000 km/year

4.5 ± 4

Descriptive

DXA, bone markers

CYC lower LS BMD Z-scores. Bone turnover markers were in a normal range.

B: case series

Heinonen et al. (1993) [19]

CYC (22); ORI (30); SKI (28); CYC (29); WL (18); CON (25)

F

18 to 32

-

-

Cross-sectional

DXA, calcium intake

CYC lower BMD at all sites than WL. No differences with CON. No relationship between BMD and calcium intake.

B: case-control

Hinrichs et al. (2010) [35]

CYC (16)

RUN (37)

TRI (22)

TEAM (62)

POW (45)

BAL (13)

STU (126)

CON (61)

M/F

17 to 30

15 h/week

12.5 h/week

15 h/week

10 h/week

10 h/week

27 h/week

7.5 h/week

-

>4

Cross-sectional

DXA

CYC low values of LS and femur BMD than the other groups

B: case-control

Maïmoun et al. (2003) [25]

CYC (11)

SWI (13)

TRI (14)

CON (10)

M

18 to 39

10.6 h/week

10.7 h/week

15.2 h/week

<2 h/week

-

Cross-sectional

DXA, hormones

CYC and TRI induce androgen deficiency compared to CON, without alteration in BMD

B: case-control

Maïmoun et al. (2004) [24]

CYC (11)

SWI (13)

TRI (14)

CON (10)

M

18 to 39

10.6 h/week

10.7 h/week

15.2 h/week

<2 h/week

9.3 ± 6.8

Cross-sectional

DXA, bone markers, calcium intake

CYC lower BAP than all groups. No differences in BMD. No relationship between BMD and calcium intake.

B: case-control

Medelli et al. (2009) [29]

CYC (73)

CON (30)

M

25.8 ± 4.3

28.3 ± 4.5

≥3 to 6 h/day

<1 h/week

-

Cross-sectional

DXA, calcium intake

CYC had higher calcium intake and lower LS and femoral neck BMD than CON.

B: case-control

Medelli et al. (2009) [4]

CYC (23)

M

28.5 ± 3.9

≥3 to 6 h/day

-

Descriptive

DXA

Two-thirds of participants had lower values of LS BMD

B: case series

Morel et al. (2001) [27]

CYC (47); other sports (657)

M

30

7 h/week

-

Cross-sectional. Sportsmen classed as amateur when 11 to 18 years old.

DXA

No differences between different sports

B: case-control, retrospective

Nevill et al. (2004) [23]

CYC (16)

CON (15)

Others (90)

M

28.6 ± 6

24.9 ± 5.4

-

>4 h/week

-

-

>3

Cross-sectional

DXA

CYC had no differences in BMD compared to CON, as other sports do

B: case-control

Nichols et al. (2003) [32]

Young CYC (16)

Master CYC (27)

CON (24)

M

31.7 ± 3.5

51.2 ± 5.3

51.2 ± 2

≥10 h/week

≥10 h/week

<2 days/week

10.9 ± 3.2

20.2 ± 8.4

-

Cross-sectional

DXA

Master CYC lower WB BMD than young CYC. Master CYC lower LS and hip BMD than young CYC and CON.

B: case-control

Nichols et al. (2010) [42]

CYC (19)

CON (18)

M

50.7 ± 4

50.7 ± 4.1

11.1 h/week

4.5 h/week

27.5 ± 6.8

Longitudinal, 7-year follow-up

DXA

Higher percentage of CYC osteopenic/osteoporotic than CON. Greater increment in this percentage in CYC.

B: case-control

Nikander et al. (2005) [26]

CYC (29)

SWI (27)

VOL (21)

HUR (24)

SQU (20)

SOC (19)

SKA (15)

AER (27)

WL (19)

ORI (29)

CRO (25)

CON (30)

F

20 to 30

10.2 ± 6.8

13.5 ± 4.5

9.9 ± 2.5

9.1 ± 2.4

6.0 ± 3.1

8.6 ± 5.5

6.4 ± 3.6

6.6 ± 3.7

8.3 ± 2.6

8.6 ± 1.4

10.9 ± 1.2

2.9 ± 2.0

5.9 ± 3.1

10.6 ± 4.3

8.6 ± 3.3

10.4 ± 3.0

6.4 ± 4.7

10.7 ± 3.8

9.4 ± 7.2

8.3 ± 2.7

3.3 ± 1.3

13.0 ± 3.1

10.7 ± 3.5

-

Cross-sectional

DXA, calcium intake

CYC and SWI no differences with CON in BMD and CSA, as the rest of the sports. No differences in calcium intake.

B: case-control

Olmedillas et al. (2011) [40]

CYC (21)

CON (23)

M

15 to 21

10 h/week

4 h/week

2 to 7

Cross-sectional

DXA

CYC lower BMC at WB, pelvis, FN and legs, and lower BMD at pelvis, hip and legs. Greater differences in CYC over 17 years compared to CON.

B: case-control

Penteado et al. (2001) [22]

CYC (31)

CON (28)

M

24

26

21 h/week

0

5.2 ± 3.3

Cross-sectional

DXA

No differences with CON.

B: case-control

Rector et al. (2008) [37]

CYC (27)

RUN (16)

M

20 to 39

≥6 h/week

≥6 h/week

>2

Cross-sectional

DXA, bone markers

CYC lower WB and LS BMD, and 7 times more likely to have osteopenia than RUN. No differences in bone turnover markers.

B: case-control

Rico et al. (1993) [20]

CYC (22)

CON (27)

M

16

≥10 h/week

-

>2

Cross-sectional

DXA, calcium intake

CYC lower legs BMC than CON, without adjustment. No differences when adjusting by weight. No relationship between BMD and calcium intake.

B: case-control

Rico et al. (1993) [50]

CYC (22)

CON (27)

M

16

≥10 h/week

-

>2

Cross-sectional

DXA

CYC lower WB BMC and BMD than CON

B: case-control

Sabo et al. (1996) [30]

CYC (6)

WL (28)

BOX (6)

CON (21)

M

21 to 24

3,000 to 10,000 km in pre-competition

-

Cross-sectional

DXA

CYC lower LS BMD than CON

B: case-control

Stewart et al. (2000) [31]

CYC (14)

RUN (12)

RUN+CYC (13)

CON (23)

M

18 to 43

8.7 h/week

10.7 h/week

9.4 h/week

0 h/week

>2

Cross-sectional

DXA

CYC lower LS BMD than CON. RUN higher WB BMD than CON. RUN+CYC higher WB BMD than CON.

B: case-control

Smathers et al. (2009) [33]

CYC (32)

CON (30)

M

20 to 45

≥1 year

3 days/week

9.4 ± 1.1

Cross-sectional

DXA, calcium intake, hormones

CYC higher calcium intake. No differences for testosterone. CYC lower LS BMD than CON.

B: case-control

Warner et al. (2002) [28]

Cross-country CYC (16)

Road CYC (14)

CON (15)

M

20 to 40

≥10 h/week

≥10 h/week

<2 h/week

5.9 ± 2.8

9.9 ± 4.4

-

Cross-sectional

DXA, hormones

Cross-country CYC higher BMD at all sites that road CYC and CON. No differences in testosterone levels.

B: case-control

Wilks et al. (2009) [46]

Sprint CYC (52)

Distance CYC (19)

CON (32)

M/F

30 to 82

50 ± 13

<2 h/week

26 ± 15

29 ± 16

Start age

Cross-sectional

pQCT

Sprint CYC higher index of strength in tibia and radius than CON. Distance CYC higher tibial BMC than CON.

B: case-control


aUnless stated, the results indicate significant differences between two or more groups.

AER = step aerobicists; BAP = bone alkaline phosphatase; BMC = bone mineral content; BMD = bone mineral density; BOX = boxers; CAN = canoeists; CIC = cyclists; CON = controls; CRO = cross-country skiers; CTX = C-terminal collagen crosslinks; DXA = dual energy X-ray absorptiometry; HUR = hurdlers; LS = lumbar spine; MRI = magnetic resonance imaging; OC = osteocalcin; ORI = orienteers; pQCT = peripheral quantitative computed tomography; RCT = randomized control trial; RUN = runners; SKA = speed skaters; SKI = skiers; SQU = squash players; SWI = swimmers; TRI = triathletes; VOL = volleyball players; WB = whole body; WL = weightlifters.

Olmedillas et al. BMC Medicine 2012 10:168   doi:10.1186/1741-7015-10-168

Open Data