The Effects of Low Energy Availability and High Impact Jumping on Markers of Bone (re)Modelling in Females

NCT04790019 | Completed

• 1 other identifier: R20-P052
• Study Type: interventional
• Target: 19
• Locations: 1 country
• Sites: 1

Brief Summary

Osteoporosis is worldwide health epidemic categorized by poor bone health, primarily diagnosed by low bone mineral density, and costs healthcare systems billions every year. Athletes and exercising people who expend large amounts of energy in physical activity, or restrict diet in order to lose weight, are at risk of low energy availability. This is when an individual fails to match their exercise energy demand with a appropriate dietary intake in order to maintain optimal physiological function; which can lead to low bone mineral density, osteoporosis both early and later in life and an increased risk of injury. Runners are particularly susceptible to stress fracture in response to low energy availability due to repetitive ground impact. Research shows that as little as five days low energy availability significantly reduces bone formation, and significantly increases bone resorption, in physically active women. The ideal solution is to restore energy availability; however, this is often very difficult during periods of intense training and conflicts with the goal of weight loss. Therefore, there is a need to develop an alternative tool to protect bone health. It is critical that any exercise intervention does not further reduce energy availability as previous research shows that this accelerates bone loss rather than prevents it. Low repetition high impact jumping exercise is highly beneficial to bone health and has been shown to improve bone structure when used as a long-term intervention in energy replete states. It takes very little time to complete and uses a very small amount of energy. However, no study to date has examined the effects of such an intervention during low energy availability. The current study will investigate whether low repetition high impact jumping prevents or reduces the reduction in bone formation and the increase in bone resorption experienced during five days of low energy availability and findings will have implications on athletic and recreational training recommendations in order to protect bone health.

Conditions

Bone Resorption; Bone Atrophy; Energy Supply; Deficiency; Female Athlete Triad; Relative Energy Deficiency in Sport

Keywords

Low energy availability; Energy restriction; Bone (re)modelling; Bone metabolism; High impact exercise

Outcome Measures

Primary Outcomes (2)

• Change in blood pro-peptide of type 1 collagen (P1NP) concentration

  P1NP is a marker of bone resorption and it will be measured during the fasted state

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

• Change in blood β-carboxyl-terminal cross-linked telopeptide of type 1 collagen (β-CTx) concentration

  β-CTx is a marker of bone formation and it will be measured during the fasted state

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

Secondary Outcomes (17)

• Change in blood 17β-oestradiol concentration

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

• Change in blood triiodothyronine (T3) concentration

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

• Change in blood β-hydroxybutyrate (β-OHB) concentration

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

• Change in blood calcium concentration

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

• Change in blood magnesium concentration

  of dietary provision to the same time on the morning following the final day of dietary provision (three days later), in each condition

Study Arms (2)

Low energy availability

EXPERIMENTAL

Intervention involves three of dietary energy restriction providing 15 kilo-calories per kilogram of fat-free mass per day.

Behavioral: Low energy availability

Low energy availability and high impact jumping

EXPERIMENTAL

Intervention involves three days of dietary energy restriction providing 15 kilo-calories per kilogram of fat-free mass per day and brief high impact jumping exercise performed daily in the morning and in the evening.

Behavioral: Low energy availability; Behavioral: High impact jumping

Interventions

Low energy availability BEHAVIORAL

Participants will be provided with food to eat every day and will not be permitted to consume any other calorie containing foods or beverages. This amount of energy contained within the food provided will be one third of that contained in the food provided in the control condition (45 kilo-calories per kilogram of fat-free mass per day) and will be standardized between and within participants for carbohydrate, protein and fat composition.

Also known as: Energy restriction

Low energy availability; Low energy availability and high impact jumping

High impact jumping BEHAVIORAL

Participants will perform a brief session of high impact jumping every morning (10 maximum effort vertical counter-movement jumps, and 5 maximum effort lateral drop jumps in each direction) and a similar session of high impact jumping every evening (20 maximum effort vertical counter-movement jumps).

Low energy availability and high impact jumping

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Menstrual cycles that are between 21 - 35 days in length for at least the previous three cycles
• Regular length of menstrual cycle (less than six days difference between cycles) for at least the previous three cycles
• Body mass index between 18.5 - 30 kg.m squared
• Weight stable for the past three months and not currently dieting

You may not qualify if:

• Smoker
• Pregnant
• Vegan
• Have used hormonal contraception at any point within the previous three months
• Regularly engage in \>3 vigorous, or \>5 moderate, exercise sessions a week
• Compete regularly in a high or multi-directional impact sport at national level or higher
• Have sustained a bone injury within the previous twelve months
• Have sustained any injury within the past six months that restricted their ability to exercise
• Taken hormone replacement therapy (HRT) at any point during the past three months
• Have been previously diagnosed with an eating disorder
• Have taken any medications (other than vitamin or mineral supplements) known to effect bone metabolism within the previous three months (e.g. glucocorticoids, anticonvulsants or anabolic steroids)
• Have previously been diagnosed with a medical condition known to impact bone health (e.g. hypothyroidism, hyperthyroidism, diabetes mellitus, hypercortisolism and renal or gastrointestinal disease)
• Have previously been diagnosed with a pathology known to impact menstrual function (e.g. primary ovarian insufficiency, hyperprolactinemia, thyroid dysfunction, polycystic ovarian syndrome and any other conditions of androgen excess)

Sponsors & Collaborators

• Loughborough University: lead

Study Sites (1)

Mark Hutson

Loughborough, Leicestershire, LE11 3TU, United Kingdom

Location

MeSH Terms

Conditions

Bone Resorption; Female Athlete Triad Syndrome; Relative Energy Deficiency in Sport

Condition Hierarchy (Ancestors)

Bone Diseases; Musculoskeletal Diseases; Feeding and Eating Disorders; Mental Disorders

Study Officials

• Richard C Blagrove, PhD

  Loughborough University

  PRINCIPAL INVESTIGATOR

• Emma O'Donnell, PhD

  Loughborough University

  STUDY DIRECTOR

• Katherine SF Brooke-Wavell, PhD

  Loughborough University

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principle Investigator

Model Details: All participants will complete the control condition and one of two experimental conditions in a randomized and counterbalanced crossover design.

Study Record Dates

• First Submitted: October 2, 2020
• First Posted: March 10, 2021
• Study Start: November 1, 2020
• Primary Completion: June 30, 2022
• Study Completion: June 30, 2022
• Last Updated: February 14, 2023

Record last verified: 2023-02

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)