Warming Up and Flexibility
Exam and Lab Practical
The professor discusses the recent exam and mentions the possibility of there being six B's in a row for the answers. He then mentions the upcoming lab practical with Dr. Mure, which starts tomorrow. The format involves either rolling a dice or discussing a list of things. He jokingly suggests charging a fee for the continued use of the "roll the dice" idea, which he believes originated from his Physiologic Assessment class. The practicals are one-on-one for an hour.
Northland ACSM Meeting and Quiz Bowl
Several students from the class attended the Northland ACSM meeting in Mano. The professor expresses his delight at seeing many juniors there, acknowledging that sports often keep undergraduates from attending out-of-town events. He then discusses the quiz bowl, a Jeopardy-style knowledge competition between schools. He congratulates the students for winning the quiz bowl, with the other team coming in fourth place. He emphasizes the importance of this victory as validation for the program's teaching methods, as there are limited opportunities to compare exercise science programs. He admits to getting some questions wrong himself and commends everyone's performance. I will make sure the trophy finds a place on display.
Final Unit and Programs
The class is now entering the final unit of material, which is a collection of miscellaneous topics. The Easter is late, only leaving two weeks of school after. The programs will be due on the last day of class. Students are encouraged to seek help if you have any questions regarding the syllabus or lectures. The professor is open to addressing questions during office hours or by appointment.
Warming Up
The lecture will cover warming up, cooling down, flexibility, and stretching. The professor mentions that this material has likely been covered in other classes or personal training experiences. The warm-up is an adjustment period between rest and activity, serving two main purposes: performance and safety (reducing the risk of injury). Research suggests that performance is generally better after a warm-up. While it seems logical that warm-ups reduce injury risk, the evidence is less clear. However, warming up is still beneficial to increase the chances of performance success.
The importance of warm-up is related to the intensity of the activity. For low-intensity activities like walking at three miles per hour, a warm-up may not be necessary. However, for high-intensity activities like a one-and-a-half-mile run test, a warm-up is crucial. It is important to find the right balance of intensity and duration in a warm-up to maximize benefits without expending unnecessary energy. This balance can depend on the individual's experience level. For example, an inexperienced marathon runner's warm-up will be different from that of an elite marathon runner. Elite runners might run several miles as a warm-up, while the untrained jogger will perform a light stationary bike workout for about 5-10 minutes.
There's an art to adequately warming someone up before a one-rep max. You would not dive straight into a one-rep max. There exist different types of warm-ups: passive and active. Passive methods increase body temperature through external means, while active methods involve exercise or movement.
Types of Warm-Up: General and Specific
Warm-ups typically begin with a general warm-up followed by a specific warm-up. A general warm-up is a low-intensity activity that doesn't need to be sport-specific, such as riding a stationary bike for 5-10 minutes with big movements. After the general warm-up, the warm-up becomes more specific to the activity, focusing on the relevant mode and intensity.
The professor provides a link to XL Athlete, a website created by a University of Minnesota colleague, that provides dynamic warm-up routines and sport-specific drills. He suggests that people should not reinvent the wheel, but make use of available resources.
Physiological Responses to Warm-Up
The warm-up should align with the intended activity. Aerobic activities require different warm-ups compared to strength training, sprinting, plyometrics, or sports-related activities. The lecture lists notable physiological effects of warming up, including:
Increased temperature
Increased blood flow
Enhanced metabolic reactions
Improved oxygen delivery
Increased hemoglobin release
Elevated heart rate and cardiac output
Post-Activation Potentiation
The lecture touches on post-activation potentiation, where motor units remain facilitated after maximal or near-maximal muscle contractions. This can be part of the warm-up or the workout itself, especially when performance is emphasized.
Static Stretching
The lecture discusses the role of static stretching in warm-ups. There are varying viewpoints on static stretching:
Stretch only before activity.
Stretch only after activity.
Stretch before and after activity.
Don't stretch ever.
Static stretching is effective for improving joint range of motion. Historically, it has been a part of most warm-up routines. However, the relationship between static stretching and performance is more nuanced. For activities requiring extreme ranges of motion (e.g., martial arts, gymnastics, dance), static stretching is essential. If the student is going into an activity that requires a lot of power it's been shown to impair performance.
Research suggests moderate to vigorous static stretching before power activities may impair performance. This could be due to decreased stiffness of the muscle-tendon unit, affecting force transmission. The professor uses the analogy of two rubber bands. Subjecting that muscle to stretching will influence force transmission:
, where $F$ is the force applied, $k$ is the spring constant (stiffness), and $x$ is the displacement or change in length
There is a good deal of potential psychological implications of something believed to be beneficial being revoked. One should come up with a personal philosophy regarding the whole topic.
Self-Myofascial Release (Foam Rolling)
The professor assigns an article reading on self-myofascial release, commonly known as foam rolling. Fascia encapsulates and protects the muscle, allowing smooth movement of tissues. Adhesions in the fascia can cause pain and impaired performance. Self-myofascial release involves using tools like foam rollers to break up these adhesions by applying mechanical force. Foam rollers have become increasingly popular as part of warm-up routines.
Percussive Therapy
Percussive therapy, using devices like mini jackhammers, that has become popular in recent years. These devices are used to address pain and tightness in muscles. While still relatively new, research is emerging to determine its effectiveness beyond the placebo effect.
Cooling Down
The cooling down phase is important, but often overlooked. It helps bring the body back to a resting state in a controlled manner, regulating hemodynamic parameters, cardiovascular dynamics, and waste removal. Cooling down is particularly crucial in clinical populations, such as individuals with cardiac disease, as adverse events can occur during this period.
Flexibility and Stretching
Flexibility is defined as the range of motion of a joint. Common flexibility tests include the sit-and-reach test. Different types of flexibility include static, dynamic, and ballistic.
Static flexibility involves holding a stretch at the end of the range of motion.
Dynamic flexibility involves range of motion during movement.
Ballistic flexibility involves explosive or bouncing movements. The importance of flexibility is debated, but maintaining appropriate muscle length and balance is crucial for proper movement patterns and posture. Extremely inflexible people are most prone to injury.
Factors Affecting Flexibility
Various factors affect flexibility, including:
Anatomy and joint structure
Muscle imbalances
Muscle control
Age
Sex (females generally more flexible)
Connective tissue
Muscle bulk
Training in limited range of motion
Activity level
Regularity of flexibility testing
The lecture emphasizes the distinction between flexibility and mobility. Flexibility refers to muscle length, while mobility encompasses how the joint moves, including tissue quality, muscle tension, muscle control, and strength. Flexibility is part of mobility, but they are not the same thing!
Active vs. Passive Stretching
Stretching can be active (you providing the force), or passive (someone else or a device is providing the force).
Stretching Types
Static: Involves holding a stretch at the end range of motion, emphasizing specific muscle groups. Effective for increasing range of motion.
Dynamic: Actively moving through the range of motion without holding end positions. Emphasizes movements specific to the activity.
Ballistic: Explosive movements to get a greater range of motion is a technique, but it's high-risk.
PNF (Proprioceptive Neuromuscular Facilitation): A contract-relax technique utilizing neurophysiological reflexes. It involves using the GTOs (Golgi Tendon Organs) to promote relaxation and increase range of motion. A clinician tells the client "I want you to try and push me as hard as you can. Try to extend that leg." The person will resist and try not to be moved. The isometric muscle action causes relaxation and promotion of a greater range of motion every time.
Recommendations and Guidelines
Flexibility exercises can be performed daily, five to seven days a week. The lecture addresses the belief that muscle mass restricts flexibility. The professor uses the example of a muscular actor who demonstrated exceptional flexibility to illustrate that muscle mass does not necessarily impede flexibility. Inflexibility is more so due to going to lift weights and not stretching.
Resources
Resources include books and websites such as exrx.net, which provide stretches to help one's performance.