Related by context. Frequent words. (Click for all words.) 42 cycling 42 exertion 42 musculoskeletal pain 41 biking 41 strenuous exercise 40 backache 40 physical exertion 40 bicycling 39 ejaculation 38 sudden cardiac death 38 cyclists 37 overtraining 37 fatigue 37 bike 37 aerobic exercises 37 muscle stiffness 36 cyclist 36 muscle soreness 36 discomfort 36 bicycle 35 calf muscles 35 VO2 max 35 pain 35 riding bicycles 35 pedaling 35 dizzy spells 35 backaches 34 carpal tunnel syndrome 34 aches pains 34 overexertion 34 muscle cramps 34 extreme tiredness 34 mental alertness 34 musculoskeletal disorders 34 muscle atrophy 34 swimming biking 33 kidney dysfunction 33 stair climbing 33 cardio respiratory 33 recumbent 33 aerobic exercise 33 bikes 33 sleep disturbances 33 sleep apnea 32 arousal 32 fainting 32 excessive daytime sleepiness 32 aching joints 32 avid cyclist 32 aerobic activity 32 nausea fatigue 32 symptoms 32 bicycles 32 fatigue nausea 32 tendonitis 32 motion sickness 32 immobility 32 lactic acid 32 joggers 32 aerobic capacity 32 aerobic fitness 32 riders 32 fluid intake 32 migraines 32 climbing stairs 31 dizziness 31 mountain biking 31 motorcyle 31 jogging 31 abnormal heartbeat 31 daytime sleepiness 31 muscle contractions 31 shin splints 31 endurance 31 sore muscles 31 stiffness 31 lower extremities 31 triathlons 31 skeletal muscles 31 riding 31 riding motorcycles 31 exerciser 31 nausea 31 nausea diarrhea 30 numbness 30 muscle spasms 30 exercisers 30 tiredness 30 frequent urination 30 hot flushes 30 roller blading 30 pedestrian fatalities 30 abdominal discomfort 30 motorcycle 30 eye irritation 30 stretching exercises 30 motorcross 30 sarcopenia 30 physiological 30 muscle 30 sleepiness