Chapter 10 Fitness and Sports Flashcards
U.S Dept of Health and Human Services: exercise guidelines for healthy Americans
1) minimum 1
50 min. per week of moderate activity or 75 min/ week vigorous, aerobic activity
2) for extensive health benefits> 300 min/ week moderate activity or combo of moderate/ vigorous
3) should include weight strengthening that involve all major muscle groups 2 days or more/ week
Plan to achieve physical fitness
1) assess current level of fitness> should speak with doctor before starting exercise program for people with health conditions such as obesity, heart disease, diabetes, hypertension etc.
2) set a goal> should set a long term goal, with smaller, broken down goals into the plan> make them measurable/realistic
3) plan the program> balanced program should include: aerobic, strength training, flexibility
3)
FITT principle
frequency, intensity time, time, type of exercise
used by physical activity experts to design a fitness program
Aerobic exercise
uses large muscle groups in rhythmic fashion to increase heart rate >aerobic means “with oxygen”
How to determine the intensity of aerobic exercise
1) calculating % of age-predicted maximum heart rate (MHR)> subtract age from 220 TIP: aim for 50%-60% MHR at initiation of aerobic exercise
Note: medications can affect heart rate calculations and safe MHR when starting the workout and throughout the workout
2) using rating of perceived exertion scale (RPE) > 0-10 scale> 0=nothing at all, 10= maximal effort, very strong exertion
Muscular endurance definition
ability of muscle to preform repeated, submaximal contractions over time without being fatigued
Muscular power
combines strength with speed for explosive movements (jumping, throwing ex.)
Recommendation time for strength training by the ACSM per week:
2-3 nonconsecutive days/ week
Flexibility
ability to move a joint through full range of motion
studies do not clearly support flexibility in preventing injury or muscle soreness> but can improve balance and stability
Warm- up benefits
- best to warm up by walking/slow jogging before anticipated activity> allows muscle filaments to slide over one another more easily> increases range of motion, flexibility
- can lower cardiovascular risks for people who arent accustomed to regular exercise
Muscle Energy Sources
ATP- main energy source for muscles> used to promote ion pumping, enzyme activity, rapid muscular contraction
ADP- cells break down ADP to make ATP from the energy taken in from food
ATP storage and resupply
phosphocreatine- used to resupply ATP> enzyme located in muscle cell that can be activated to split (PCr) into phosphate and creatine> disadvantage: not much made and stored in muscle: athletes usually supplement creatine
Limited oxygen supply in muscle causes:
- Glucose can be used for energy to the muscle and is broken down into: pyruvic acid> accumulates and is converted to lactic acid
- fastest way to resupply ATP
- provides most of the energy needed for quick bursts of energy ranging from 30 sec to 2 min
2 major disadvantages of anaerobic processes:
high rate of ATP production cannot be sustained for long periods
rapid accumulation of lactic acid increases the acidity of muscle> higher acidity decreases activity of key enzymes in muscle cells
lactic acid build up in muscles are released into the bloodstream> liver can take up some of the lactic acid and resynthesize into glucose > glucose then can re-enter the bloodstream to be used for cell uptake and breakdown
Products of aerobic glucose breakdown
water and carbon dioxide
- energy is released more slowly> can sustain for even hours at steady pace
