2MA, CSCS Baltimore Veterans Health Care Center, Baltimore MD
3PT, MS, PhD Asheville Veterans Health Care Center, Asheville NC
Numerous investigations report an association between CrossFit® style training and improvements in health and wellbeing [4-6]as well an in increase in exercise enjoyment and adherence [7]. Despite the widespread popularity of CrossFit® and reported physical and mental health evidenced based realizations, CrossFit® programs may be implicated in high injury rates associated with high exercise intensity, volume and repetition including muscle, tendon, ligament injury. Additionally, Exertional Rhabdomyolysis (ERM), a rapid deterioration of skeletal muscle, potentially leading to electrolyte imbalances, mental status changes, compartment syndrome, kidney impairment, cardiac arrhythmias and even arrest may occur during CrossFit® training [8-10].
Why is it important for rehabilitation practitioners to understand the basic CrossFit® training principles as we certainly cannot understand the biomechanics and training regimes of all client fitness training activities? This survey with 610 responses provides client reported data regarding CrossFit® training: patterns, experience level, incidence (per 1000 hours), injury locations, age, sex, return to activity, and perceptions of practitioner knowledge of exercise rigor demand. Our anticipated outcome is to assist practitioners establish an optimal plan for both preventive and rehabilitation of associated CrossFit® training injuries. One study purpose was to better understand CrossFit® related injuries, specifically, factors impacting athletes’ injury rates (e.g. training volume and fitness level) and to assess potential associations between injury risk and athlete demographics and training behaviors. An additional objective sought insight into self-reported injury management choices including medical professionals consulted after injury, athletes’ return to sport decisions, and perceptions regarding healthcare providers’ knowledge of CrossFit® training demands. This information is potentially valuable to clinicians interested in optimizing injured CrossFit® athlete management.
Frequency counts were calculated to obtain the demographic profile of survey respondents (Figure 1) and injury incidence. Chi square analysis was performed to evaluate response differences for each survey question using a p-value of 0.05 to determine statistical significance.
610 individuals responded to the online survey from July 2017 through October 2017. Survey respondents were mainly female (65.6%), ages 30-59 (80%) who participated in CrossFit® for 4 or more years (56%). Thirty-sevenpercent of respondents identified CrossFit® training volumes of 4-6 hours per week with most (87%) reporting training at a CrossFit® affiliate(Table 1).
Table 1: Demographic Profile |
|||
|
Frequency |
Percent |
p-value |
Gender |
210 |
34.4% |
0.01 |
Age |
3 |
0.5% |
0.01 |
CrossFit Years |
34 |
5.6% |
0.01 |
Hours per week |
59 |
9.7% |
0.01 |
Training Level |
13 |
2.1% |
0.01 |
Figure 1:Self-Reported Survey Injury Rate per 1000 Training Hours |
|
Number of training hours per week |
Injuries per 1000 hours |
3 or less |
3.6 |
4-6 |
2.66 -1.77 |
7-10 |
1.47- 0.98 |
10 or more hours |
0.98 |
Individuals reporting injuries, 57% (189) continued to train despite their injury, while 40.2% (131) reported stopping CrossFit® training temporarily, returning after the injury resolved. Overwhelmingly, athletes assumed personal responsibility for their injury, attributing injury cause to overtraining (37%) and/ or their own poor choices (39%), rather than an issue with coaching, programming, or methodology. Regardless of injury, almost all survey respondents reported a higher fitness level with CrossFit® training. Fitness levels prior to starting CrossFit® training were minimal for 26% of respondents, moderate for 54%, and excellent for 12%. After participating in CrossFit® training only 3% described their fitness levels as minimal, while 45% self-reported moderate fitness and 52% described themselves in excellent fitness (Figure-2).
A significant percentage (87.4%) of CrossFit® athletes who reported injuries indicated they sought professional injury treatment (χ2 = 86.113, df =1, p < 0.01). Physical therapists (39.9%), chiropractors (17.1%), massage therapists (14.9%), andorthopedic surgeons (12.7%) were medical providers most frequently consulted, though primary care physicians (7.6%) and athletic trainers (3.9%) were also utilized for injury diagnosis and management. Only 40% of individuals seeking professional medical care believed their healthcare provider held a high understanding of CrossFit® training physical demands, while 26% reported their health care provider displayed low knowledge of CrossFit® methodology and training approach with chiropractors reported to hold the highest knowledge. Providers in the "other" category, were considered to demonstrate the lowest knowledge of CrossFit®’s training methodology(Figure-3)
Table 2: Injury Vs. CrossFit Years/Gender/Age/Weekly Training Hour |
||
CrossFit® Years |
Injuries |
Percent |
0-6 months |
12 |
12/34 = 35.29% |
6 months- 1 year |
30 |
30/62 = 48.39% |
1-2 years |
55 |
55/103 = 53.40% |
2-4 years |
98 |
98/183 = 53.55% |
> 4 years |
139 |
139/228 = 60.96% |
TOTAL |
334 |
334/610 |
|
|
p= 0.041 |
Gender |
|
|
Male |
123 |
123/210 = 58.57% |
Female |
211 |
211/400= 52.75% |
TOTAL |
334 |
334/610 |
|
|
p = 0.17 |
Age (y) |
|
|
<18 |
1 |
1/3 = 33.33% |
18-29 |
42 |
42/89 = 47.19% |
30-39 |
77 |
77/163 = 47.24% |
40-49 |
114 |
114/178 = 64.04% |
50-59 |
81 |
81/143 = 56.64% |
60+ |
19 |
19/34 = 55.88% |
TOTAL |
334 |
334/610 |
|
|
p = 0.026 |
|
|
|
Hours Per week |
|
|
<3 |
32 |
32/59= 54.24% |
4-6 hours |
191 |
191/343 = 55.69% |
7-10 hours |
84 |
84/156 = 53.85% |
> 10 hours |
27 |
27/52 = 51.92% |
TOTAL |
334 |
334/610 |
|
|
p = 0.951 |
|
Table 3:Injury Site and Occurence |
||
Injury Site |
Number of Injuries |
Percent |
Neck |
26 |
4.11% |
Back |
122 |
19.27% |
Shoulder |
179 |
28.28% |
Elbow |
46 |
7.27% |
Wrist/Hand |
54 |
8.53% |
Hip |
31 |
4.90% |
Knee |
82 |
12.95% |
Ankle/Foot |
45 |
7.11% |
Other |
48 |
7.58% |
Total Injuries |
633 |
100% |
P < 0.01 |
Figure 4: Evidence based Reported Injury Rate per Team Sport |
|
Activity |
Injuries per 1000 hours |
Basketball |
14 |
Rugby |
12–53 |
Recreational Running |
11 |
Football |
9.6 |
Strongman |
4.5-6.1 |
Soccer |
0.5–13.7 |
CrossFit |
0.98-3.6 |
1) How long have you been participating in CrossFit® training?
a) ___0-6 months
b) ___6month- 1 year
c) ___1-2 years
d) ___2-4 years
e) ___>4 years
2) Gender
a) ___female
b) ___male
3) Age
a) ___<18
b) ____18-29
c) ___30-39
d) ___40-49
e) ___50-59
f) ___>60
4) Height
a) < 5’
b) 5’0” -5’2”
c) 5’3”-5’4”
d) 5’5” –5’6”
e) 5’7”- 5’8”
f) 5’9”-5’10”
g) 5’11” - 6’1”
h) > 6’2”
5) Weight
a) <110 lbs
b) 110 to 125 lbs
c) 126 to 140 lbs
d) 141 to 165 lbs
e) 166 to 180 lbs
f) 181> 200 lbs
g) 201-225 lbs
h) 225-250
i) >250
6) How many hours per week do you train?
a) 3 hours or less
b) 4 to 6 hours
c) 7-10 hours
d) More than 10 hours
7) What is your typical training level?
a) Foundations/beginner
b) Scaled
c) Intermediate
d) RX
e) RX +/Elite
8) Do you compete in CrossFit® and/or Functional Fitness Competitions, if so, what division? (check all that apply)
a) Yes, scaled division in competitions
b) Yes, Rx division in competitions
c) Top 1000 in CrossFit® open scaled division
d) Top 1000 in CrossFit® open Rx division
e) Regional/games competitor
f) I do not compete in CrossFit®®
9) What was your level of fitness prior to beginning a CrossFit® training program?
a) Did not exercise
b) Minimal fitness
c) Moderate fitness
d) Excellent fitness
10) Where do you do the majority of your training?
a. CrossFit® affiliate
b. Unaffiliated CrossFit®box
c. Traditional fitness facility/gym
d. Home/garage gym
e. Other
11) What is your level of fitness now?
a) Do not exercise
b) Minimal fitness
c) Moderate fitness
d) Excellent fitness
12) Do you do you train in other sports or fitness activities concurrently with CrossFit® (e.g., running, biking, powerlifting, Olympic lifting, team sports, etc...)?
a) Yes
b) No
13) Have you ever sustained an injury as a direct result of CrossFit®training (not including hand tears, rips. rope burns, banged/cut shins, sore joints, and/or chipped teeth)
a) yes
b) no
14) If yes, please indicate body part injured (list all injured areas)
a) Neck
b) Back
c) Shoulder
d) Elbow
e) Wrist/hand
f) Hip
g) Knee
h) Ankle/foot
i) Other (please specify)
15) What type of injury (select any/all that apply)
a) tendonitis
b) Muscle, tendon, or ligament tear or rupture
c) disc problems
d) nerve problems
e) Bone problem (fracture)
f) Joint problem (cartilage/meniscus)
g) Other (please specify)
16) Was your injury a direct result of your:
a) programming
b) coaching
c) overtraining
d) Unknown
e) Other (please specify reason for each injury if more than one injury has been sustained)
17) Did this injury require treatment?
a) Yes
b) No
18) What healthcare provider(s) addressed your injury (check all that apply)
a) physical therapist
b) orthopedic physician/surgeon
c) chiropractor
d) primary care physician
e) athletic trainer/personal trainer
f) massage therapist
19) What level of understanding do you believe your healthcare provider(s) holds regarding the physical demands of your training style?
a) high
b) moderate
c) low
20) Did your injury require you to stop training?
a) Yes, never returned
b) Yes, temporarily but able to return
c) No, able to continue to train around injury or with modifications
d) No, continued to train with the injury/no change in program
21) What level of training/skill did you return to after your injury?
a) Lower level
b) Prior level
c) Higher level
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